fix(cli): keep opencode2 as a working alias

fix(cli): clarify opencode2 rename guidance
docs: use stable V2 packages (#48576 )
2026-09-12 03:46:22 +00:00 · 2026-09-11 20:55:03 -04:00 · 2026-09-11 20:50:20 -04:00 · 2026-09-11 20:33:18 -04:00 · 2026-09-11 19:46:37 -04:00 · 2026-09-11 19:10:23 -04:00
202 changed files with 3977 additions and 2675 deletions
@@ -25,7 +25,7 @@ on:
        required: false
        type: string

-concurrency: ${{ github.workflow }}-${{ github.ref }}-${{ inputs.version || inputs.bump }}
+concurrency: ${{ github.workflow }}-${{ github.ref }}-${{ (github.ref_name == 'v2' && (inputs.version || inputs.bump) && 'release') || inputs.version || inputs.bump }}

 permissions:
  id-token: write
@@ -33,7 +33,7 @@ permissions:
  packages: write

 env:
-  OPENCODE_CHANNEL: ${{ (github.ref_name == 'v2' && 'dev') || '' }}
+  OPENCODE_CHANNEL: ${{ (github.ref_name == 'v2' && !inputs.bump && !inputs.version && 'dev') || '' }}

 jobs:
  version:
@@ -168,7 +168,7 @@ jobs:
          fi

          found=0
-          for file in packages/cli/dist/cli-darwin-*/bin/opencode2; do
+          for file in packages/cli/dist/cli-darwin-*/bin/opencode; do
            if [ ! -f "$file" ]; then
              continue
            fi
@@ -191,7 +191,7 @@ jobs:

      - uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
        with:
-          name: opencode-preview-cli
+          name: opencode-preview-cli-macos
          path: packages/cli/dist/cli-*
          if-no-files-found: error

@@ -199,7 +199,7 @@ jobs:
    needs: version
    runs-on: blacksmith-4vcpu-ubuntu-2404
    timeout-minutes: 30
-    if: github.repository == 'anomalyco/opencode'
+    if: github.repository == 'anomalyco/opencode' && !(github.ref_name == 'v2' && (inputs.bump || inputs.version))
    steps:
      - uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0

@@ -221,7 +221,7 @@ jobs:
    needs:
      - version
      - build-node-app-archive
-    if: github.repository == 'anomalyco/opencode'
+    if: github.repository == 'anomalyco/opencode' && !(github.ref_name == 'v2' && (inputs.bump || inputs.version))
    strategy:
      fail-fast: false
      matrix:
@@ -276,10 +276,9 @@ jobs:

  sign-cli-windows:
    needs:
-      - build-cli
-      - version
+      - sign-cli-macos
    runs-on: blacksmith-4vcpu-windows-2025
-    if: github.repository == 'anomalyco/opencode' && github.ref_name != 'v2' && github.ref_name != 'beta'
+    if: github.repository == 'anomalyco/opencode' && (github.ref_name == 'v2' || github.ref_name == 'beta')
    env:
      AZURE_CLIENT_ID: ${{ secrets.AZURE_CLIENT_ID }}
      AZURE_TENANT_ID: ${{ secrets.AZURE_TENANT_ID }}
@@ -292,15 +291,8 @@ jobs:

      - uses: actions/download-artifact@d3f86a106a0bac45b974a628896c90dbdf5c8093 # v4.3.0
        with:
-          name: opencode-cli-windows
-          path: packages/opencode/dist
-
-      - name: Setup git committer
-        id: committer
-        uses: ./.github/actions/setup-git-committer
-        with:
-          opencode-app-id: ${{ vars.OPENCODE_APP_ID }}
-          opencode-app-secret: ${{ secrets.OPENCODE_APP_SECRET }}
+          name: opencode-preview-cli-macos
+          path: packages/cli/dist

      - name: Azure login
        uses: azure/login@a457da9ea143d694b1b9c7c869ebb04ebe844ef5 # v2.3.0
@@ -315,9 +307,9 @@ jobs:
          signing-account-name: ${{ env.AZURE_TRUSTED_SIGNING_ACCOUNT_NAME }}
          certificate-profile-name: ${{ env.AZURE_TRUSTED_SIGNING_CERTIFICATE_PROFILE }}
          files: |
-            ${{ github.workspace }}\packages\opencode\dist\opencode-windows-arm64\bin\opencode.exe
-            ${{ github.workspace }}\packages\opencode\dist\opencode-windows-x64\bin\opencode.exe
-            ${{ github.workspace }}\packages\opencode\dist\opencode-windows-x64-baseline\bin\opencode.exe
+            ${{ github.workspace }}\packages\cli\dist\cli-windows-arm64\bin\opencode.exe
+            ${{ github.workspace }}\packages\cli\dist\cli-windows-x64\bin\opencode.exe
+            ${{ github.workspace }}\packages\cli\dist\cli-windows-x64-baseline\bin\opencode.exe
          exclude-environment-credential: true
          exclude-workload-identity-credential: true
          exclude-managed-identity-credential: true
@@ -333,9 +325,9 @@ jobs:
        shell: pwsh
        run: |
          $files = @(
-            "${{ github.workspace }}\packages\opencode\dist\opencode-windows-arm64\bin\opencode.exe",
-            "${{ github.workspace }}\packages\opencode\dist\opencode-windows-x64\bin\opencode.exe",
-            "${{ github.workspace }}\packages\opencode\dist\opencode-windows-x64-baseline\bin\opencode.exe"
+            "${{ github.workspace }}\packages\cli\dist\cli-windows-arm64\bin\opencode.exe",
+            "${{ github.workspace }}\packages\cli\dist\cli-windows-x64\bin\opencode.exe",
+            "${{ github.workspace }}\packages\cli\dist\cli-windows-x64-baseline\bin\opencode.exe"
          )

          foreach ($file in $files) {
@@ -345,40 +337,17 @@ jobs:
            }
          }

-      - name: Repack Windows CLI archives
-        working-directory: packages/opencode/dist
-        shell: pwsh
-        run: |
-          Compress-Archive -Path "opencode-windows-arm64\bin\*" -DestinationPath "opencode-windows-arm64.zip" -Force
-          Compress-Archive -Path "opencode-windows-x64\bin\*" -DestinationPath "opencode-windows-x64.zip" -Force
-          Compress-Archive -Path "opencode-windows-x64-baseline\bin\*" -DestinationPath "opencode-windows-x64-baseline.zip" -Force
-
-      - name: Upload signed Windows CLI release assets
-        if: needs.version.outputs.release != ''
-        shell: pwsh
-        env:
-          GH_TOKEN: ${{ steps.committer.outputs.token }}
-        run: |
-          gh release upload "v${{ needs.version.outputs.version }}" `
-            "${{ github.workspace }}\packages\opencode\dist\opencode-windows-arm64.zip" `
-            "${{ github.workspace }}\packages\opencode\dist\opencode-windows-x64.zip" `
-            "${{ github.workspace }}\packages\opencode\dist\opencode-windows-x64-baseline.zip" `
-            --clobber `
-            --repo "${{ needs.version.outputs.repo }}"
-
      - uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
        with:
-          name: opencode-cli-signed-windows
-          path: |
-            packages/opencode/dist/opencode-windows-arm64
-            packages/opencode/dist/opencode-windows-x64
-            packages/opencode/dist/opencode-windows-x64-baseline
+          name: opencode-preview-cli
+          path: packages/cli/dist/cli-*
+          if-no-files-found: error

  build-electron:
    needs:
      - version
-      - sign-cli-macos
-    if: github.repository == 'anomalyco/opencode' && github.ref_name != 'v2'
+      - sign-cli-windows
+    if: github.repository == 'anomalyco/opencode' && (github.ref_name != 'v2' || needs.version.outputs.release != '')
    continue-on-error: false
    env:
      AZURE_CLIENT_ID: ${{ secrets.AZURE_CLIENT_ID }}
@@ -8,9 +8,9 @@

 ## Live V2 TUI Testing

- Run `bun run dev:live` from a development worktree to test its TUI against the currently elected `opencode2` background server and live sessions.
+- Run `bun run dev:live` from a development worktree to test its TUI against the currently elected `opencode` background server and live sessions.
 - Pass a directory after the script when needed, for example `bun run dev:live /path/to/project`.
- The script discovers the server with `opencode2 service status`, injects its private local credential from `opencode2 service get password`, and uses the `dev` TUI storage channel so tabs and other client-local state match the installed client.
+- The script discovers the server with `opencode service status`, injects its private local credential from `opencode service get password`, and uses the `dev` TUI storage channel so tabs and other client-local state match the installed client.
 - Prefer `dev:live` over plain `bun run dev` for this workflow. An implicit managed-service connection may replace the live server when the worktree client version differs; explicit `--server` warns and continues without replacing it.

 ## V2 TUI Stories
@@ -31,7 +31,7 @@
    },
    "packages/ai": {
      "name": "@opencode/ai",
-      "version": "1.17.20",
+      "version": "2.0.0",
      "dependencies": {
        "@aws-sdk/credential-providers": "3.1057.0",
        "@opencode/schema": "workspace:*",
@@ -53,7 +53,7 @@
    },
    "packages/app": {
      "name": "@opencode/app",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@corvu/drawer": "catalog:",
        "@dnd-kit/abstract": "0.5.0",
@@ -111,7 +111,7 @@
    },
    "packages/cli": {
      "name": "@opencode/cli",
-      "version": "1.18.4",
+      "version": "2.0.0",
      "bin": {
        "opencode2": "./bin/opencode2.cjs",
      },
@@ -175,7 +175,7 @@
    },
    "packages/client": {
      "name": "@opencode/client",
-      "version": "1.17.13",
+      "version": "2.0.0",
      "dependencies": {
        "@opencode/protocol": "workspace:*",
        "@opencode/schema": "workspace:*",
@@ -201,7 +201,7 @@
    },
    "packages/codemode": {
      "name": "@opencode/codemode",
-      "version": "1.18.4",
+      "version": "2.0.0",
      "dependencies": {
        "acorn": "8.15.0",
        "effect": "catalog:",
@@ -215,7 +215,7 @@
    },
    "packages/console/app": {
      "name": "@opencode/console-app",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@cloudflare/vite-plugin": "1.15.2",
        "@ibm/plex": "6.4.1",
@@ -251,7 +251,7 @@
    },
    "packages/console/core": {
      "name": "@opencode/console-core",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@aws-sdk/client-sts": "3.782.0",
        "@jsx-email/render": "1.1.1",
@@ -278,7 +278,7 @@
    },
    "packages/console/function": {
      "name": "@opencode/console-function",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@openauthjs/openauth": "0.0.0-20250322224806",
        "@opencode/console-core": "workspace:*",
@@ -295,7 +295,7 @@
    },
    "packages/console/mail": {
      "name": "@opencode/console-mail",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@jsx-email/all": "2.2.3",
        "@jsx-email/cli": "1.4.3",
@@ -319,7 +319,7 @@
    },
    "packages/console/support": {
      "name": "@opencode/console-support",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@cloudflare/vite-plugin": "1.15.2",
        "@opencode/console-core": "workspace:*",
@@ -339,7 +339,7 @@
    },
    "packages/core": {
      "name": "@opencode/core",
-      "version": "1.18.4",
+      "version": "2.0.0",
      "dependencies": {
        "@ai-sdk/alibaba": "1.0.17",
        "@ai-sdk/anthropic": "3.0.82",
@@ -411,7 +411,7 @@
    },
    "packages/desktop": {
      "name": "@opencode/desktop",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@zip.js/zip.js": "2.7.62",
        "electron-context-menu": "4.1.2",
@@ -463,7 +463,7 @@
    },
    "packages/enterprise": {
      "name": "@opencode/enterprise",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@hono/standard-validator": "catalog:",
        "@opencode-ai/sdk": "1.18.21",
@@ -500,7 +500,7 @@
    },
    "packages/function": {
      "name": "@opencode/function",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@octokit/auth-app": "8.0.1",
        "@octokit/rest": "catalog:",
@@ -516,7 +516,7 @@
    },
    "packages/http-recorder": {
      "name": "@opencode/http-recorder",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@effect/platform-node-shared": "4.0.0-rc.112",
      },
@@ -535,7 +535,7 @@
    },
    "packages/httpapi-codegen": {
      "name": "@opencode/httpapi-codegen",
-      "version": "0.0.0",
+      "version": "2.0.0",
      "dependencies": {
        "effect": "catalog:",
        "prettier": "3.6.2",
@@ -548,7 +548,7 @@
    },
    "packages/latex": {
      "name": "@opencode/latex",
-      "version": "0.0.0",
+      "version": "2.0.0",
      "dependencies": {
        "@opencode/plugin": "workspace:*",
        "@opentui/core": "catalog:",
@@ -562,7 +562,7 @@
    },
    "packages/merman": {
      "name": "@opencode/merman",
-      "version": "0.0.0",
+      "version": "2.0.0",
      "dependencies": {
        "@opencode/plugin": "workspace:*",
        "@opentui/core": "catalog:",
@@ -577,7 +577,7 @@
    },
    "packages/plugin": {
      "name": "@opencode/plugin",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@ai-sdk/provider": "3.0.8",
        "@opencode/ai": "workspace:*",
@@ -616,7 +616,7 @@
    },
    "packages/plugin-browser": {
      "name": "@opencode/plugin-browser",
-      "version": "0.0.0",
+      "version": "2.0.0",
      "dependencies": {
        "@opencode/plugin": "workspace:*",
        "@opencode/schema": "workspace:*",
@@ -646,7 +646,7 @@
    },
    "packages/protocol": {
      "name": "@opencode/protocol",
-      "version": "1.17.11",
+      "version": "2.0.0",
      "dependencies": {
        "@opencode/schema": "workspace:*",
        "effect": "catalog:",
@@ -661,7 +661,7 @@
    },
    "packages/schema": {
      "name": "@opencode/schema",
-      "version": "1.17.11",
+      "version": "2.0.0",
      "dependencies": {
        "@standard-schema/spec": "catalog:",
        "effect": "catalog:",
@@ -685,7 +685,7 @@
    },
    "packages/sdk": {
      "name": "@opencode/sdk",
-      "version": "1.18.4",
+      "version": "2.0.0",
      "dependencies": {
        "@opencode/client": "workspace:*",
        "@opencode/core": "workspace:*",
@@ -706,7 +706,7 @@
    },
    "packages/server": {
      "name": "@opencode/server",
-      "version": "1.18.4",
+      "version": "2.0.0",
      "dependencies": {
        "@effect/platform-node": "catalog:",
        "@effect/platform-node-shared": "catalog:",
@@ -728,7 +728,7 @@
    },
    "packages/session-ui": {
      "name": "@opencode/session-ui",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@kobalte/core": "catalog:",
        "@opencode/client": "workspace:*",
@@ -763,7 +763,7 @@
    },
    "packages/simulation": {
      "name": "@opencode/simulation",
-      "version": "1.17.13",
+      "version": "2.0.0",
      "dependencies": {
        "@opencode/ai": "workspace:*",
        "@opencode/core": "workspace:*",
@@ -783,7 +783,7 @@
    },
    "packages/stats/app": {
      "name": "@opencode/stats-app",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@ibm/plex": "6.4.1",
        "@kobalte/core": "catalog:",
@@ -817,7 +817,7 @@
    },
    "packages/stats/core": {
      "name": "@opencode/stats-core",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@aws-sdk/client-athena": "3.933.0",
        "@planetscale/database": "1.19.0",
@@ -836,7 +836,7 @@
    },
    "packages/stats/server": {
      "name": "@opencode/stats-server",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@aws-sdk/client-firehose": "3.933.0",
        "@effect/platform-node": "catalog:",
@@ -882,7 +882,7 @@
    },
    "packages/theme": {
      "name": "@opencode/theme",
-      "version": "0.0.0",
+      "version": "2.0.0",
      "dependencies": {
        "@opentui/core": "catalog:",
        "effect": "catalog:",
@@ -896,7 +896,7 @@
    },
    "packages/tui": {
      "name": "@opencode/tui",
-      "version": "1.18.4",
+      "version": "2.0.0",
      "dependencies": {
        "@opencode/client": "workspace:*",
        "@opencode/core": "workspace:*",
@@ -931,7 +931,7 @@
    },
    "packages/ui": {
      "name": "@opencode/ui",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@kobalte/core": "catalog:",
        "@pierre/diffs": "catalog:",
@@ -966,7 +966,7 @@
    },
    "packages/util": {
      "name": "@opencode/util",
-      "version": "1.18.3",
+      "version": "2.0.0",
      "dependencies": {
        "@effect/opentelemetry": "catalog:",
        "@effect/platform-node": "catalog:",
@@ -999,7 +999,7 @@
    },
    "packages/web": {
      "name": "@opencode/web",
-      "version": "1.18.15",
+      "version": "2.0.0",
      "dependencies": {
        "@astrojs/cloudflare": "12.6.3",
        "@astrojs/markdown-remark": "6.3.1",
@@ -1040,7 +1040,7 @@
    },
    "services/update": {
      "name": "@opencode/update",
-      "version": "1.18.4",
+      "version": "2.0.0",
      "dependencies": {
        "jose": "6.0.11",
        "semver": "catalog:",
@@ -1,6 +1,7 @@
 #!/usr/bin/env bash
 set -euo pipefail
-APP=opencode2
+APP=opencode
+SOURCE_APP=opencode

 MUTED='\033[0;2m'
 RED='\033[0;31m'
@@ -22,7 +23,7 @@ Options:
 Examples:
    curl -fsSL https://opencode.ai/v2/install | bash
    curl -fsSL https://opencode.ai/v2/install | bash -s -- --version 0.0.0-beta-17236
-    ./install --binary /path/to/opencode2
+    ./install --binary /path/to/opencode
 EOF
 }

@@ -201,9 +202,9 @@ else

    filename="cli-$target-$specific_version.tgz"
    url="https://registry.npmjs.org/$package_name/-/$filename"
-    binary_name="$APP"
+    binary_name="$SOURCE_APP"
    if [ "$os" = "windows" ]; then
-        binary_name="$APP.exe"
+        binary_name="$SOURCE_APP.exe"
    fi
 fi

@@ -230,12 +231,7 @@ check_version() {
        installed_version="${installed_version##* }"
        installed_version="${installed_version#v}"

-        if [[ "$installed_version" != "$specific_version" ]]; then
-            print_message info "${MUTED}Installed version: ${NC}$installed_version."
-        else
-            print_message info "${MUTED}Version ${NC}$specific_version${MUTED} already installed"
-            exit 0
-        fi
+        print_message info "${MUTED}Installed version: ${NC}$installed_version."
    fi
 }

@@ -340,15 +336,46 @@ download_and_install() {
    fi

    tar -xzf "$tmp_dir/$filename" -C "$tmp_dir"
-    mv "$tmp_dir/package/bin/$binary_name" "$INSTALL_DIR"
-    chmod 755 "${INSTALL_DIR}/$binary_name"
+    local installed_binary="$APP"
+    if [ "$os" = "windows" ]; then
+        installed_binary="$APP.exe"
+    fi
+    mv "$tmp_dir/package/bin/$binary_name" "$INSTALL_DIR/$installed_binary"
+    chmod 755 "$INSTALL_DIR/$installed_binary"
    rm -rf "$tmp_dir"
 }

 install_from_binary() {
    print_message info "\n${MUTED}Installing ${NC}$APP ${MUTED}from: ${NC}$binary_path"
-    cp "$binary_path" "${INSTALL_DIR}/$APP"
-    chmod 755 "${INSTALL_DIR}/$APP"
+    local installed_binary="$APP"
+    case "$(uname -s)" in
+        MINGW*|MSYS*|CYGWIN*) installed_binary="$APP.exe" ;;
+    esac
+    cp "$binary_path" "$INSTALL_DIR/$installed_binary"
+    chmod 755 "$INSTALL_DIR/$installed_binary"
+}
+
+install_legacy_shim() {
+    local shim_os="${os:-}"
+    if [[ -z "$shim_os" ]]; then
+        case "$(uname -s)" in
+            MINGW*|MSYS*|CYGWIN*) shim_os="windows" ;;
+        esac
+    fi
+    rm -f "$INSTALL_DIR/opencode2" "$INSTALL_DIR/opencode2.exe" "$INSTALL_DIR/opencode2.cmd"
+    if [[ "$shim_os" == "windows" ]]; then
+        cat > "$INSTALL_DIR/opencode2.cmd" <<'EOF'
+@echo off
+"%~dp0opencode.exe" %*
+exit /b %errorlevel%
+EOF
+        return
+    fi
+    cat > "$INSTALL_DIR/opencode2" <<'EOF'
+#!/bin/sh
+exec "$(dirname "$0")/opencode" "$@"
+EOF
+    chmod 755 "$INSTALL_DIR/opencode2"
 }

 if [ -n "$binary_path" ]; then
@@ -357,6 +384,7 @@ else
    check_version
    download_and_install
 fi
+install_legacy_shim


 add_to_path() {
@@ -453,7 +481,7 @@ echo -e ""
 echo -e "${MUTED}OpenCode includes free models, to start:${NC}"
 echo -e ""
 echo -e "cd <project>  ${MUTED}# Open directory${NC}"
-echo -e "opencode2     ${MUTED}# Run command${NC}"
+echo -e "opencode      ${MUTED}# Run command${NC}"
 echo -e ""
 echo -e "${MUTED}For more information visit ${NC}https://opencode.ai/v2/docs"
 echo -e ""
@@ -2,15 +2,15 @@
  "$schema": "https://json.schemastore.org/package.json",
  "name": "opencode",
  "description": "AI-powered development tool",
-  "version": "0.0.0",
+  "version": "2.0.0",
  "private": true,
  "type": "module",
  "packageManager": "bun@1.4.2",
  "scripts": {
    "dev": "bun run --cwd packages/cli src/index.ts",
-    "dev:live": "sh -c 'OPENCODE_TUI_CHANNEL=dev OPENCODE_PASSWORD=\"$(opencode2 service get password)\" exec bun run dev \"$@\" --server \"$(opencode2 service status)\"' --",
+    "dev:live": "sh -c 'OPENCODE_TUI_CHANNEL=dev OPENCODE_PASSWORD=\"$(opencode service get password)\" exec bun run dev \"$@\" --server \"$(opencode service status)\"' --",
    "dev:vite": "bun run --cwd packages/cli --conditions=browser dev/vite.ts",
-    "dev:vite:live": "sh -c 'OPENCODE_TUI_CHANNEL=dev OPENCODE_PASSWORD=\"$(opencode2 service get password)\" exec bun run dev:vite \"$@\" --server \"$(opencode2 service status)\"' --",
+    "dev:vite:live": "sh -c 'OPENCODE_TUI_CHANNEL=dev OPENCODE_PASSWORD=\"$(opencode service get password)\" exec bun run dev:vite \"$@\" --server \"$(opencode service status)\"' --",
    "dev:desktop": "bun --cwd packages/desktop dev",
    "dev:web": "bun --cwd packages/app dev",
    "dev:console": "ulimit -n 10240 2>/dev/null; bun run --cwd packages/console/app dev",
@@ -122,13 +122,14 @@ Keep provider facades small and explicit:

 ### Provider Package Entrypoints

-Catalog-selected native providers use package-like export paths from `@opencode/ai`. They are internal entrypoints in one npm package, not separately published provider packages. Every entrypoint implements `ProviderPackage.Definition` and exposes `model(modelID, settings)`, where settings are serializable provider configuration plus common `headers`, `body`, and `limits` overlays.
+Catalog-selected native providers use package-like export paths from `@opencode/ai`. They are internal entrypoints in one npm package, not separately published provider packages. Every entrypoint implements `ProviderPackage.Definition` and exposes `model(modelID, settings)`, where settings are one flat serializable object: the connection keys the entrypoint declares (`apiKey`, `baseURL`, `region`, …), the common `headers` and `body` overlays, and the protocol's request options (`reasoningEffort`, `thinking`, …) side by side. Each entrypoint destructures its own connection keys and passes the rest to the route as `providerOptions`; there is no nested `providerOptions` at the entrypoint.

 ```ts
 import { model } from "@opencode/ai/providers/openai/responses"

 const selected = model("gpt-5", {
  apiKey,
+  reasoningEffort: "high",
 })
 ```

@@ -1,6 +1,6 @@
 {
  "$schema": "https://json.schemastore.org/package.json",
-  "version": "1.17.20",
+  "version": "2.0.0",
  "name": "@opencode/ai",
  "type": "module",
  "license": "MIT",
@@ -1708,7 +1708,10 @@ export const transport = <
 }

 function requiredBetaHeaders(body: Pick<AnthropicMessagesBody, "messages" | "context_management" | "thinking">) {
-  const betas: string[] = []
+  // Always request interleaved thinking. The API accepts the header on any
+  // model and ignores it where unsupported, while manual-thinking models need
+  // it for thinking between tool calls.
+  const betas: string[] = ["interleaved-thinking-2025-05-14"]
  const requestsCompaction = (body.context_management?.edits.length ?? 0) > 0
  const replaysCompaction = body.messages.some((message) =>
    message.content.some((block) => block.type === "compaction"),
@@ -1,6 +1,10 @@
 import type { LanguageModel, ProviderOptions } from "./schema/index.js"
 import type { CompactionOperations } from "./route/client.js"

+/**
+ * Flat, serializable settings for `model(modelID, settings)`. Each entrypoint declares the connection keys it
+ * reads; every other key is a request option for the route's protocol.
+ */
 export interface Settings extends Readonly<Record<string, unknown>> {
  readonly baseURL?: string
  readonly headers?: Readonly<Record<string, string>>
@@ -1,3 +1,4 @@
+import { Struct } from "effect"
 import type { ProviderPackage } from "../provider-package.js"
 import { AlibabaChat } from "../protocols/alibaba-chat.js"
 import { AlibabaMessages } from "../protocols/alibaba-messages.js"
@@ -34,9 +35,9 @@ export type Config = Location &
    readonly providerOptions?: ChatOptionsInput | MessagesOptionsInput | ResponsesOptionsInput
  }
 export type Settings<Options = ChatOptionsInput> = Location &
-  ProviderPackage.Settings & {
+  ProviderPackage.Settings &
+  Options & {
    readonly apiKey?: string
-    readonly providerOptions?: Options
  }

 const hosts = new Map<string, string>([
@@ -120,7 +121,11 @@ export const responsesModel: ProviderPackage.Definition<

 function fromSettings(input: Settings<Config["providerOptions"]>) {
  const { body, ...rest } = input
-  return configure({ ...rest, http: body === undefined ? undefined : { body } })
+  return configure({
+    ...rest,
+    http: body === undefined ? undefined : { body },
+    providerOptions: Struct.omit(rest, ["apiKey", "baseURL", "headers", "region", "workspaceID"]),
+  })
 }

 export const webSearch = () => hostedTool("web_search", "Search the web with Alibaba's hosted search tool.")
@@ -23,16 +23,16 @@ export type Config = RouteDefaultsInput & {
  readonly providerOptions?: OpenAIProviderOptionsInput
 }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly auth?: "bearer" | "sigv4"
-  readonly baseURL?: string
-  readonly credentials?: Credentials
-  readonly profile?: string
-  readonly region?: string
-  readonly topP?: number
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly auth?: "bearer" | "sigv4"
+    readonly baseURL?: string
+    readonly credentials?: Credentials
+    readonly profile?: string
+    readonly region?: string
+    readonly topP?: number
+  }

 const responsesRoute = Route.make({
  id: "bedrock-mantle-responses",
@@ -108,18 +108,29 @@ export const configure = (input: Config = {}) => {

 export const provider = configure()

-const fromSettings = (settings: Settings) =>
+const fromSettings = ({
+  apiKey,
+  auth,
+  baseURL,
+  body,
+  credentials,
+  headers,
+  profile,
+  region,
+  topP,
+  ...providerOptions
+}: Settings) =>
  configure({
-    apiKey: settings.apiKey,
-    auth: settings.auth,
-    baseURL: settings.baseURL,
-    credentials: settings.credentials,
-    generation: settings.topP === undefined ? undefined : { topP: settings.topP },
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    profile: settings.profile,
-    providerOptions: settings.providerOptions,
-    region: settings.region,
+    apiKey,
+    auth,
+    baseURL,
+    credentials,
+    generation: topP === undefined ? undefined : { topP },
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    profile,
+    providerOptions,
+    region,
  })

 export const chatModel: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
@@ -19,13 +19,13 @@ export type Config = RouteDefaultsInput &
  }

 export type Settings = ProviderPackage.Settings &
+  AnthropicMessages.ProviderOptionsInput &
  (
    | { readonly apiKey?: string; readonly authToken?: never }
    | { readonly apiKey?: never; readonly authToken?: string }
  ) & {
    readonly baseURL: string
    readonly provider?: string
-    readonly providerOptions?: AnthropicMessages.ProviderOptionsInput
  }

 export const routes = [AnthropicMessages.route]
@@ -63,22 +63,20 @@ export const provider = {

 export const model: ProviderPackage.Definition<Settings, AnthropicMessages.ProviderOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, authToken, baseURL, body, headers, provider, ...providerOptions },
 ) => {
-  // Read before the exclusivity check narrows a conflicting settings object to `never`.
-  const provider = ProviderID.make(settings.provider ?? id)
-  if (settings.apiKey !== undefined && settings.authToken !== undefined)
+  if (apiKey !== undefined && authToken !== undefined)
    throw new ProviderConfigurationError({
-      provider,
+      provider: ProviderID.make(provider ?? id),
      message: "Anthropic-compatible apiKey cannot be combined with authToken",
    })
  return configure({
-    ...(settings.authToken === undefined ? { apiKey: settings.apiKey } : { auth: Auth.bearer(settings.authToken) }),
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    provider: settings.provider,
-    providerOptions: settings.providerOptions,
+    ...(authToken === undefined ? { apiKey: apiKey } : { auth: Auth.bearer(authToken) }),
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    provider,
+    providerOptions,
  }).model(modelID)
 }

@@ -21,12 +21,12 @@ export type Config = RouteDefaultsInput &
  }

 export type Settings = ProviderPackage.Settings &
+  AnthropicMessages.ProviderOptionsInput &
  (
    | { readonly apiKey?: string; readonly authToken?: never }
    | { readonly apiKey?: never; readonly authToken?: string }
  ) & {
    readonly baseURL?: string
-    readonly providerOptions?: AnthropicMessages.ProviderOptionsInput
  }

 const auth = (options: ProviderAuthOption<"optional">) => {
@@ -54,18 +54,18 @@ export const configure = (input: Config = {}) => {
 export const provider = configure()
 export const model: ProviderPackage.Definition<Settings, AnthropicMessages.ProviderOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, authToken, baseURL, body, headers, ...providerOptions },
 ) => {
-  if (settings.apiKey !== undefined && settings.authToken !== undefined)
+  if (apiKey !== undefined && authToken !== undefined)
    throw new ProviderConfigurationError({
      provider: id,
      message: "Anthropic apiKey cannot be combined with authToken",
    })
  return configure({
-    ...(settings.authToken === undefined ? { apiKey: settings.apiKey } : { auth: Auth.bearer(settings.authToken) }),
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    ...(authToken === undefined ? { apiKey: apiKey } : { auth: Auth.bearer(authToken) }),
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)
 }
@@ -28,12 +28,12 @@ export type LanguageModelOptions = AzureURL &
 export type Config = LanguageModelOptions

 export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput &
  AzureURL & {
    readonly apiKey?: string
    readonly apiVersion?: string
    readonly queryParams?: Readonly<Record<string, string>>
    readonly useDeploymentBasedUrls?: boolean
-    readonly providerOptions?: OpenAIProviderOptionsInput
  }

 const resourceBaseURL = (resourceName: string) => `https://${resourceName.trim()}.openai.azure.com/openai`
@@ -151,18 +151,28 @@ export const provider = {
  configure,
 }

-const config = (settings: Settings): Config => {
+const config = ({
+  apiKey,
+  apiVersion,
+  baseURL,
+  body,
+  headers,
+  queryParams,
+  resourceName,
+  useDeploymentBasedUrls,
+  ...providerOptions
+}: Settings): Config => {
  const common = {
-    apiKey: settings.apiKey,
-    apiVersion: settings.apiVersion,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
-    queryParams: settings.queryParams === undefined ? undefined : { ...settings.queryParams },
-    useDeploymentBasedUrls: settings.useDeploymentBasedUrls,
+    apiKey,
+    apiVersion,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
+    queryParams: queryParams === undefined ? undefined : { ...queryParams },
+    useDeploymentBasedUrls,
  }
-  if (settings.baseURL !== undefined) return { ...common, baseURL: settings.baseURL }
-  if (settings.resourceName !== undefined) return { ...common, resourceName: settings.resourceName }
+  if (baseURL !== undefined) return { ...common, baseURL }
+  if (resourceName !== undefined) return { ...common, resourceName }
  throw new ProviderConfigurationError({ provider: id, message: "Azure requires resourceName or baseURL" })
 }

@@ -15,11 +15,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: OpenAIProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 export const route = Route.make({
  id: "baseten-chat",
@@ -48,13 +48,16 @@ export const configure = (input: LanguageModelOptions = {}) => {

 export const provider = configure()

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export * as Baseten from "./baseten.js"
@@ -15,11 +15,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: OpenAIProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 export const route = Route.make({
  id: "cerebras-chat",
@@ -52,11 +52,14 @@ export const configure = (input: LanguageModelOptions = {}) => {

 export const provider = configure()

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)
@@ -27,10 +27,10 @@ export type LanguageModelOptions = GatewayURL &
  }

 export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput &
  GatewayURL & {
    readonly apiKey?: string
    readonly gatewayApiKey?: string
-    readonly providerOptions?: OpenAIProviderOptionsInput
  }

 export const baseURL = (input: GatewayURL) => {
@@ -89,14 +89,25 @@ export const configure = (input: LanguageModelOptions) => {

 export const provider = { id, configure }

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
-  configure({
-    apiKey: settings.apiKey,
-    gatewayApiKey: settings.gatewayApiKey,
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) => {
+  const {
+    accountId: _,
+    apiKey,
+    baseURL: _url,
+    body,
+    gatewayApiKey,
+    gatewayId: _id,
+    headers,
+    ...providerOptions
+  } = settings
+  return configure({
+    apiKey,
+    gatewayApiKey,
    baseURL: baseURL(settings),
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)
+}

 export * as CloudflareAIGateway from "./cloudflare-ai-gateway.js"
@@ -21,9 +21,9 @@ export type LanguageModelOptions = WorkersAIURL &
  }

 export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput &
  WorkersAIURL & {
    readonly apiKey?: string
-    readonly providerOptions?: OpenAIProviderOptionsInput
  }

 export const baseURL = (input: WorkersAIURL) => {
@@ -63,13 +63,15 @@ export const configure = (input: LanguageModelOptions) => {

 export const provider = { id, configure }

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
-  configure({
-    apiKey: settings.apiKey,
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) => {
+  const { accountId: _, apiKey, baseURL: _url, body, headers, ...providerOptions } = settings
+  return configure({
+    apiKey,
    baseURL: baseURL(settings),
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)
+}

 export * as CloudflareWorkersAI from "./cloudflare-workers-ai.js"
@@ -15,11 +15,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: OpenAIProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 export const route = Route.make({
  id: "deepinfra-chat",
@@ -55,11 +55,14 @@ export const configure = (input: LanguageModelOptions = {}) => {

 export const provider = configure()

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)
@@ -15,11 +15,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: OpenAIProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 export const route = Route.make({
  id: "deepseek-chat",
@@ -52,13 +52,16 @@ export const configure = (input: LanguageModelOptions = {}) => {

 export const provider = configure()

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export * as DeepSeek from "./deepseek.js"
@@ -15,11 +15,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: OpenAIProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 export const route = Route.make({
  id: "fireworks-chat",
@@ -48,13 +48,16 @@ export const configure = (input: LanguageModelOptions = {}) => {

 export const provider = configure()

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export * as Fireworks from "./fireworks.js"
@@ -16,14 +16,14 @@ export type Config = RouteDefaultsInput &
    readonly providerOptions?: OpenAIProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly accessToken?: string
-  readonly apiKey?: never
-  readonly baseURL?: string
-  readonly location?: string
-  readonly project?: string
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly accessToken?: string
+    readonly apiKey?: never
+    readonly baseURL?: string
+    readonly location?: string
+    readonly project?: string
+  }

 const route = Route.make({
  id: "google-vertex-chat",
@@ -74,16 +74,19 @@ export const provider = {
  configure,
 }

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) => {
-  if (settings.apiKey !== undefined)
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
+  modelID,
+  { accessToken, apiKey, baseURL, body, headers, location, project, ...providerOptions },
+) => {
+  if (apiKey !== undefined)
    throw new ProviderConfigurationError({ provider: id, message: "Google Vertex Chat does not support API keys" })
  return configure({
-    accessToken: settings.accessToken,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    location: settings.location,
-    project: settings.project,
-    providerOptions: settings.providerOptions,
+    accessToken,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    location,
+    project,
+    providerOptions,
  }).model(modelID)
 }
@@ -25,14 +25,14 @@ export type Config = RouteDefaultsInput &
    readonly providerOptions?: AnthropicMessages.ProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly accessToken?: string
-  readonly apiKey?: never
-  readonly baseURL?: string
-  readonly location?: string
-  readonly project?: string
-  readonly providerOptions?: AnthropicMessages.ProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  AnthropicMessages.ProviderOptionsInput & {
+    readonly accessToken?: string
+    readonly apiKey?: never
+    readonly baseURL?: string
+    readonly location?: string
+    readonly project?: string
+  }

 const route = Route.make({
  id: "google-vertex-messages",
@@ -105,17 +105,17 @@ export const provider = {

 export const model: ProviderPackage.Definition<Settings, AnthropicMessages.ProviderOptionsInput>["model"] = (
  modelID,
-  settings,
+  { accessToken, apiKey, baseURL, body, headers, location, project, ...providerOptions },
 ) => {
-  if (settings.apiKey !== undefined)
+  if (apiKey !== undefined)
    throw new ProviderConfigurationError({ provider: id, message: "Google Vertex Messages does not support API keys" })
  return configure({
-    accessToken: settings.accessToken,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    location: settings.location,
-    project: settings.project,
-    providerOptions: settings.providerOptions,
+    accessToken,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    location,
+    project,
+    providerOptions,
  }).model(modelID)
 }
@@ -16,14 +16,14 @@ export type Config = RouteDefaultsInput &
    readonly providerOptions?: OpenResponsesProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly accessToken?: string
-  readonly apiKey?: never
-  readonly baseURL?: string
-  readonly location?: string
-  readonly project?: string
-  readonly providerOptions?: OpenResponsesProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenResponsesProviderOptionsInput & {
+    readonly accessToken?: string
+    readonly apiKey?: never
+    readonly baseURL?: string
+    readonly location?: string
+    readonly project?: string
+  }

 const route = Route.make({
  id: "google-vertex-responses",
@@ -77,17 +77,17 @@ export const provider = {

 export const model: ProviderPackage.Definition<Settings, OpenResponsesProviderOptionsInput>["model"] = (
  modelID,
-  settings,
+  { accessToken, apiKey, baseURL, body, headers, location, project, ...providerOptions },
 ) => {
-  if (settings.apiKey !== undefined)
+  if (apiKey !== undefined)
    throw new ProviderConfigurationError({ provider: id, message: "Google Vertex Responses does not support API keys" })
  return configure({
-    accessToken: settings.accessToken,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    location: settings.location,
-    project: settings.project,
-    providerOptions: settings.providerOptions,
+    accessToken,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    location,
+    project,
+    providerOptions,
  }).model(modelID)
 }
@@ -26,6 +26,7 @@ export type Config = RouteDefaultsInput &
  }

 export type Settings = ProviderPackage.Settings &
+  GeminiProviderOptionsInput &
  (
    | { readonly accessToken?: string; readonly apiKey?: never }
    | { readonly accessToken?: never; readonly apiKey?: string }
@@ -33,7 +34,6 @@ export type Settings = ProviderPackage.Settings &
    readonly baseURL?: string
    readonly location?: string
    readonly project?: string
-    readonly providerOptions?: GeminiProviderOptionsInput
  }

 const fromRequest = Effect.fn("GoogleVertex.fromRequest")(function* (request: LLMRequest) {
@@ -124,19 +124,22 @@ export const provider = {
  id,
  configure,
 }
-export const model: ProviderPackage.Definition<Settings, GeminiProviderOptionsInput>["model"] = (modelID, settings) => {
-  if (settings.apiKey !== undefined && settings.accessToken !== undefined)
+export const model: ProviderPackage.Definition<Settings, GeminiProviderOptionsInput>["model"] = (
+  modelID,
+  { accessToken, apiKey, baseURL, body, headers, location, project, ...providerOptions },
+) => {
+  if (apiKey !== undefined && accessToken !== undefined)
    throw new ProviderConfigurationError({
      provider: id,
      message: "Google Vertex apiKey cannot be combined with accessToken or auth",
    })
  return configure({
-    ...(settings.apiKey === undefined ? { accessToken: settings.accessToken } : { apiKey: settings.apiKey }),
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    location: settings.location,
-    project: settings.project,
-    providerOptions: settings.providerOptions,
+    ...(apiKey === undefined ? { accessToken: accessToken } : { apiKey: apiKey }),
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    location,
+    project,
+    providerOptions,
  }).model(modelID)
 }
@@ -20,11 +20,11 @@ export type Config = RouteDefaultsInput &
    readonly providerOptions?: Gemini.ProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: Gemini.ProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  Gemini.ProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 const auth = (options: ProviderAuthOption<"optional">) => {
  if ("auth" in options && options.auth) return options.auth
@@ -57,13 +57,16 @@ export const configure = (input: Config = {}) => {
 }

 export const provider = configure()
-export const model: ProviderPackage.Definition<Settings, Gemini.ProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, Gemini.ProviderOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export const image = provider.image
@@ -26,11 +26,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: ProviderOptions
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: ProviderOptions
-}
+export type Settings = ProviderPackage.Settings &
+  ProviderOptions & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 const Options = Schema.Struct({
  includeReasoning: Schema.optional(Schema.Boolean),
@@ -103,13 +103,16 @@ export const configure = (input: LanguageModelOptions = {}) => {

 export const provider = configure()

-export const model: ProviderPackage.Definition<Settings, ProviderOptions>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, ProviderOptions>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export * as Groq from "./groq.js"
@@ -79,11 +79,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: ProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: ProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  ProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 const responsesRoute = Route.make({
  id: "meta-responses",
@@ -169,13 +169,13 @@ export const chatModel: ProviderPackage.Definition<Settings, OpenResponsesProvid
 export const messagesModel: ProviderPackage.Definition<Settings, MessagesOptionsInput>["model"] = (modelID, settings) =>
  fromSettings(settings).messages(modelID)

-function fromSettings(settings: Settings) {
+function fromSettings({ apiKey, baseURL, body, headers, ...providerOptions }: Settings) {
  return configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  })
 }

@@ -40,11 +40,11 @@ export type Config = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: ProviderOptionsInput
  }

-export interface Settings<Options = MessagesOptionsInput> extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: Options
-}
+export type Settings<Options = MessagesOptionsInput> = ProviderPackage.Settings &
+  Options & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 const ChatOptions = Schema.Struct({
  thinking: Schema.optional(Schema.Struct({ type: Schema.String })),
@@ -127,14 +127,14 @@ export const provider = configure()

 export const model: ProviderPackage.Definition<Settings<MessagesOptionsInput>, MessagesOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, baseURL, body, headers, ...providerOptions },
 ) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export const messages = provider.messages
@@ -3,11 +3,14 @@ import { MiniMax } from "../minimax.js"

 export type Settings = MiniMax.Settings<MiniMax.ChatOptionsInput>

-export const model: ProviderPackage.Definition<Settings, MiniMax.ChatOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, MiniMax.ChatOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  MiniMax.configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).chat(modelID)
@@ -5,12 +5,12 @@ export type Settings = MiniMax.Settings<MiniMax.ResponsesOptionsInput>

 export const model: ProviderPackage.Definition<Settings, MiniMax.ResponsesOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, baseURL, body, headers, ...providerOptions },
 ) =>
  MiniMax.configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).responses(modelID)
@@ -14,11 +14,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: ProviderOptions
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: ProviderOptions
-}
+export type Settings = ProviderPackage.Settings &
+  ProviderOptions & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 export const route = MistralChat.route
 export const routes = [route]
@@ -39,13 +39,16 @@ export const configure = (input: LanguageModelOptions = {}) => {

 export const provider = configure()

-export const model: ProviderPackage.Definition<Settings, ProviderOptions>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, ProviderOptions>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export * as Mistral from "./mistral.js"
@@ -42,11 +42,11 @@ export type Config = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: ChatOptionsInput | MessagesOptionsInput | ResponsesOptionsInput
  }

-export interface Settings<Options = ChatOptionsInput> extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: Options
-}
+export type Settings<Options = ChatOptionsInput> = ProviderPackage.Settings &
+  Options & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 const ChatOptions = Schema.Struct({
  reasoningEffort: Schema.optional(Schema.String),
@@ -133,13 +133,16 @@ export const chat = provider.chat
 export const messages = provider.messages
 export const responses = provider.responses

-export const model: ProviderPackage.Definition<Settings, ChatOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, ChatOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export * as Moonshot from "./moonshot.js"
@@ -5,12 +5,12 @@ export type Settings = Moonshot.Settings<Moonshot.MessagesOptionsInput>

 export const model: ProviderPackage.Definition<Settings, Moonshot.MessagesOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, baseURL, body, headers, ...providerOptions },
 ) =>
  Moonshot.configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).messages(modelID)
@@ -5,12 +5,12 @@ export type Settings = Moonshot.Settings<Moonshot.ResponsesOptionsInput>

 export const model: ProviderPackage.Definition<Settings, Moonshot.ResponsesOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, baseURL, body, headers, ...providerOptions },
 ) =>
  Moonshot.configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).responses(modelID)
@@ -16,12 +16,12 @@ export type Config = RouteDefaultsInput &
    readonly providerOptions?: OpenResponsesProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL: string
-  readonly provider?: string
-  readonly providerOptions?: OpenResponsesProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenResponsesProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL: string
+    readonly provider?: string
+  }

 export const routes = [OpenAICompatibleResponses.route]

@@ -48,13 +48,13 @@ export const provider = {

 export const model: ProviderPackage.Definition<Settings, OpenResponsesProviderOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, baseURL, body, headers, provider, ...providerOptions },
 ) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    provider: settings.provider,
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    provider,
+    providerOptions,
  }).model(modelID)
@@ -14,12 +14,12 @@ type GenericModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: OpenAIProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL: string
-  readonly provider?: string
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL: string
+    readonly provider?: string
+  }

 export const routes = [OpenAICompatibleChat.route]

@@ -45,14 +45,17 @@ export const provider = {
  configure,
 }

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, provider, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    provider: settings.provider,
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    provider,
+    providerOptions,
  }).model(modelID)

 export * as OpenAICompatible from "./openai-compatible.js"
@@ -57,14 +57,14 @@ export const imageGeneration = (options: ImageGenerationOptions = {}) =>
    },
  })

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly organization?: string
-  readonly project?: string
-  readonly queryParams?: Readonly<Record<string, string>>
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+    readonly organization?: string
+    readonly project?: string
+    readonly queryParams?: Readonly<Record<string, string>>
+  }

 const auth = (options: ProviderAuthOption<"optional">) => AuthOptions.bearer(options, "OPENAI_API_KEY")

@@ -116,19 +116,28 @@ export const configure = (input: Config = {}) => {

 export const provider = configure()

-const config = (settings: Settings): Config => {
+const config = ({
+  apiKey,
+  baseURL,
+  body,
+  headers: given,
+  organization,
+  project,
+  queryParams,
+  ...providerOptions
+}: Settings): Config => {
  const headers = {
-    ...(settings.organization === undefined ? {} : { "OpenAI-Organization": settings.organization }),
-    ...(settings.project === undefined ? {} : { "OpenAI-Project": settings.project }),
-    ...settings.headers,
+    ...(organization === undefined ? {} : { "OpenAI-Organization": organization }),
+    ...(project === undefined ? {} : { "OpenAI-Project": project }),
+    ...given,
  }
  return {
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
+    apiKey,
+    baseURL,
    headers: Object.keys(headers).length === 0 ? undefined : headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
-    queryParams: settings.queryParams === undefined ? undefined : { ...settings.queryParams },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
+    queryParams: queryParams === undefined ? undefined : { ...queryParams },
  }
 }

@@ -77,11 +77,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: OpenRouterProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: OpenRouterProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenRouterProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 const OpenRouterBody = Schema.StructWithRest(Schema.Struct(OpenAIChat.bodyFields), [
  Schema.Record(Schema.String, Schema.Any),
@@ -191,12 +191,12 @@ export const configure = (input: LanguageModelOptions = {}) => {
 export const provider = configure()
 export const model: ProviderPackage.Definition<Settings, OpenRouterProviderOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, baseURL, body, headers, ...providerOptions },
 ) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)
@@ -15,11 +15,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: OpenAIProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: OpenAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  OpenAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 export const route = Route.make({
  id: "togetherai-chat",
@@ -52,11 +52,14 @@ export const configure = (input: LanguageModelOptions = {}) => {

 export const provider = configure()

-export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, OpenAIProviderOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers === undefined ? undefined : { ...settings.headers },
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers: headers === undefined ? undefined : { ...headers },
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)
@@ -20,11 +20,11 @@ export type LanguageModelOptions = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: XAIProviderOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: XAIProviderOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  XAIProviderOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 export type { XAIImageOptions } from "../protocols/xai-images.js"

@@ -110,13 +110,13 @@ export const model: ProviderPackage.Definition<
  Settings,
  XAIProviderOptionsInput,
  typeof responsesRoute.compact
->["model"] = (modelID, settings) =>
+>["model"] = (modelID, { apiKey, baseURL, body, headers, ...providerOptions }) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)
 export const responses = provider.responses
 export const chat = provider.chat
@@ -23,11 +23,11 @@ export type Config = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: ChatOptionsInput | MessagesOptionsInput | ResponsesOptionsInput
  }

-export interface Settings<Options = ChatOptionsInput> extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: Options
-}
+export type Settings<Options = ChatOptionsInput> = ProviderPackage.Settings &
+  Options & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 const chatRoute = Route.make({
  id: "zai-coding-chat",
@@ -80,13 +80,16 @@ export const chat = provider.chat
 export const messages = provider.messages
 export const responses = provider.responses

-export const model: ProviderPackage.Definition<Settings, ChatOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, ChatOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export * as ZAICodingPlan from "./zai-coding-plan.js"
@@ -5,12 +5,12 @@ export type Settings = ZAICodingPlan.Settings<ZAICodingPlan.MessagesOptionsInput

 export const model: ProviderPackage.Definition<Settings, ZAICodingPlan.MessagesOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, baseURL, body, headers, ...providerOptions },
 ) =>
  ZAICodingPlan.configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).messages(modelID)
@@ -5,12 +5,12 @@ export type Settings = ZAICodingPlan.Settings<ZAICodingPlan.ResponsesOptionsInpu

 export const model: ProviderPackage.Definition<Settings, ZAICodingPlan.ResponsesOptionsInput>["model"] = (
  modelID,
-  settings,
+  { apiKey, baseURL, body, headers, ...providerOptions },
 ) =>
  ZAICodingPlan.configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).responses(modelID)
@@ -17,11 +17,11 @@ export type Config = Omit<RouteDefaultsInput, "providerOptions"> &
    readonly providerOptions?: ChatOptionsInput
  }

-export interface Settings extends ProviderPackage.Settings {
-  readonly apiKey?: string
-  readonly baseURL?: string
-  readonly providerOptions?: ChatOptionsInput
-}
+export type Settings = ProviderPackage.Settings &
+  ChatOptionsInput & {
+    readonly apiKey?: string
+    readonly baseURL?: string
+  }

 export type { ZAIImageOptions } from "../protocols/zai-images.js"

@@ -70,13 +70,16 @@ export const provider = configure()
 export const image = provider.image
 export const chat = provider.chat

-export const model: ProviderPackage.Definition<Settings, ChatOptionsInput>["model"] = (modelID, settings) =>
+export const model: ProviderPackage.Definition<Settings, ChatOptionsInput>["model"] = (
+  modelID,
+  { apiKey, baseURL, body, headers, ...providerOptions },
+) =>
  configure({
-    apiKey: settings.apiKey,
-    baseURL: settings.baseURL,
-    headers: settings.headers,
-    http: settings.body === undefined ? undefined : { body: { ...settings.body } },
-    providerOptions: settings.providerOptions,
+    apiKey,
+    baseURL,
+    headers,
+    http: body === undefined ? undefined : { body: { ...body } },
+    providerOptions,
  }).model(modelID)

 export * as ZAI from "./zai.js"
@@ -188,13 +188,13 @@ describe("provider package entrypoints", () => {
      baseURL: "https://provider.example.test/v1/",
      headers: { "x-application": "opencode" },
      body: { service_tier: "priority" },
-      providerOptions: { reasoningEffort: "high" as const },
+      reasoningEffort: "high" as const,
    }
    const deepinfra = DeepInfra.model("google/gemma-3-27b-it", settings)

    expect(deepinfra.route.id).toBe("deepinfra-chat")
    expect(deepinfra.route.endpoint.baseURL).toBe("https://provider.example.test/v1/openai")
-    expect(deepinfra.route.defaults.providerOptions).toEqual(settings.providerOptions)
+    expect(deepinfra.route.defaults.providerOptions).toEqual({ reasoningEffort: "high" })
    expect(deepinfra.route.defaults.headers).toEqual(settings.headers)
    expect(deepinfra.route.defaults.http?.body).toEqual(settings.body)
  })
@@ -210,7 +210,7 @@ describe("provider package entrypoints", () => {
        apiKey: "fixture",
        headers: { "x-application": "opencode" },
        body: { custom: true },
-        providerOptions: { reasoningEffort: "high" },
+        reasoningEffort: "high",
      })
      expect(selected.provider).toBe(provider.id)
      expect(selected.route.endpoint.baseURL).toBe(provider.baseURL({ accountId: "account" }))
@@ -231,11 +231,11 @@ describe("provider package entrypoints", () => {
    }
    const openrouter = OpenRouter.model("anthropic/claude-sonnet-4", {
      ...settings,
-      providerOptions: { usage: true },
+      usage: true,
    })
    const xai = XAI.model("grok-4", {
      ...settings,
-      providerOptions: { reasoningEffort: "high" },
+      reasoningEffort: "high",
    })

    for (const selected of [openrouter, xai]) {
@@ -269,7 +269,8 @@ describe("provider package entrypoints", () => {
      provider: "example",
      headers: { "x-application": "opencode" },
      body: { service_tier: "priority" },
-      providerOptions: { reasoningEffort: "low", store: true },
+      reasoningEffort: "low",
+      store: true,
    })

    expect(String(selected.provider)).toBe("example")
@@ -295,7 +296,7 @@ describe("provider package entrypoints", () => {
      provider: "example",
      headers: { "x-application": "opencode" },
      body: { metadata: { user_id: "user_1" } },
-      providerOptions: { effort: "low" },
+      effort: "low",
    })

    expect(String(selected.provider)).toBe("example")
@@ -315,7 +316,7 @@ describe("provider package entrypoints", () => {
    const Anthropic = await import("@opencode/ai/providers/anthropic")
    const selected = Anthropic.model("claude-sonnet-4-6", {
      apiKey: "fixture",
-      providerOptions: { thinking: { type: "adaptive" } },
+      thinking: { type: "adaptive" },
    })

    expect(selected.route.defaults.providerOptions).toEqual({ thinking: { type: "adaptive" } })
@@ -409,7 +410,7 @@ describe("provider package entrypoints", () => {
      baseURL: "https://generativelanguage.test/v1beta",
      headers: { "x-application": "opencode" },
      body: { safetySettings: [] },
-      providerOptions: { thinkingConfig: { thinkingBudget: 1_024 } },
+      thinkingConfig: { thinkingBudget: 1_024 },
    })

    expect(selected.route.id).toBe("gemini")
@@ -69,7 +69,9 @@ for (const model of [
      dynamicResponse(({ request, text, respond }) =>
        Effect.sync(() => {
          const body = JSON.parse(text)
-          expect(request.headers["anthropic-beta"]).toBe("existing-beta,compact-2026-01-12")
+          expect(request.headers["anthropic-beta"]).toBe(
+            "existing-beta,interleaved-thinking-2025-05-14,compact-2026-01-12",
+          )
          if (body.messages.length === 1) {
            expect(body.context_management.edits).toEqual([
              {
@@ -32,7 +32,9 @@ for (const [id, enabled] of [
        enabled ? { type: "adaptive", block_binding: { prefix_mismatch_behavior: "drop_block" } } : undefined,
      )
      expect(prepared.request.headers["anthropic-beta"]).toBe(
-        enabled ? "existing-beta,thinking-binding-controls-2026-08-01" : "existing-beta",
+        enabled
+          ? "existing-beta,interleaved-thinking-2025-05-14,thinking-binding-controls-2026-08-01"
+          : "existing-beta,interleaved-thinking-2025-05-14",
      )
    }),
  )
@@ -53,7 +55,9 @@ it.effect("preserves explicit thinking settings and combines required beta heade
      const prepared = yield* AnthropicMessages.route.prepareTransport(compiled.body, request)
      expect(compiled.body.thinking).toEqual(thinking)
      expect(prepared.request.headers["anthropic-beta"]).toBe(
-        thinking.type === "disabled" ? "compact-2026-01-12" : "compact-2026-01-12,thinking-binding-controls-2026-08-01",
+        thinking.type === "disabled"
+          ? "interleaved-thinking-2025-05-14,compact-2026-01-12"
+          : "interleaved-thinking-2025-05-14,compact-2026-01-12,thinking-binding-controls-2026-08-01",
      )
    }
  }),
@@ -34,12 +34,10 @@ it.effect("Groq lowers its own options for custom catalog identities and endpoin
        baseURL: "https://gateway.example/v1",
        headers: { "x-client": "test" },
        body: { custom: "value" },
-        providerOptions: {
-          reasoningEffort: "default",
-          parallelToolCalls: true,
-          serviceTier: "flex",
-          user: "test-user",
-        },
+        reasoningEffort: "default",
+        parallelToolCalls: true,
+        serviceTier: "flex",
+        user: "test-user",
      }),
      { provider: "custom-groq" },
    )
@@ -87,7 +87,7 @@ it.effect("Meta package selectors preserve overrides and Chat token policy on cu
        baseURL: "https://gateway.example/v1",
        headers: { "x-client": "test" },
        body: { custom: "value" },
-        providerOptions: { reasoningEffort: "future-effort" },
+        reasoningEffort: "future-effort",
      })
      expect(model.route.endpoint.baseURL).toBe("https://gateway.example/v1")
      expect(model.route.defaults.headers).toEqual({ "x-client": "test" })
@@ -99,7 +99,7 @@ describe("native OpenAI-compatible providers", () => {
        const settings = {
          apiKey: "fixture",
          baseURL: "https://gateway.example/v1",
-          providerOptions: { reasoningEffort: "high" },
+          reasoningEffort: "high",
        }
        const selected = provider.configure(settings).model("test-model")
        expect(selected.provider).toBe(provider.id)
@@ -143,7 +143,7 @@ describe("native OpenAI-compatible providers", () => {
          tools: [
            ToolDefinition.make({ name: "lookup", description: "Look up data", inputSchema: { type: "object" } }),
          ],
-          providerOptions: { store: true },
+          store: true,
        }),
      )

@@ -168,7 +168,7 @@ describe("native OpenAI-compatible providers", () => {
            ]),
            Message.user("Continue."),
          ],
-          providerOptions: { store: true },
+          store: true,
        }),
      )

@@ -206,7 +206,7 @@ describe("native OpenAI-compatible providers", () => {
        baseURL: "https://gateway.example/v1",
        headers: { "x-application": "opencode" },
        body: { service_tier: "priority" },
-        providerOptions: { reasoningEffort: "high" },
+        reasoningEffort: "high",
      })

      expect(selected.route.endpoint.baseURL).toBe("https://gateway.example/v1")
@@ -1,6 +1,6 @@
 {
  "name": "@opencode/app",
-  "version": "1.18.15",
+  "version": "2.0.0",
  "description": "",
  "type": "module",
  "exports": {
@@ -285,7 +285,7 @@ export const DESKTOP_NATIVE_ENGLISH = {
  "desktop.updater.dialog.later": "Later",

  "desktop.cli.installed.title": "CLI Installed",
-  "desktop.cli.installed.message": "CLI installed to {{path}}\n\nRestart your terminal to use the 'opencode2' command.",
+  "desktop.cli.installed.message": "CLI installed to {{path}}\n\nRestart your terminal to use the 'opencode' command.",
  "desktop.cli.failed.title": "Installation Failed",
  "desktop.cli.failed.message": "Failed to install CLI: {{error}}",

@@ -0,0 +1,16 @@
+FROM alpine AS base
+
+ARG BUN_RUNTIME_TRANSPILER_CACHE_PATH=0
+ENV BUN_RUNTIME_TRANSPILER_CACHE_PATH=${BUN_RUNTIME_TRANSPILER_CACHE_PATH}
+RUN apk add --no-cache libgcc libstdc++ ripgrep
+
+FROM base AS build-amd64
+COPY dist/cli-linux-x64-baseline-musl/bin/opencode /usr/local/bin/opencode
+
+FROM base AS build-arm64
+COPY dist/cli-linux-arm64-musl/bin/opencode /usr/local/bin/opencode
+
+ARG TARGETARCH
+FROM build-${TARGETARCH}
+RUN ln -s opencode /usr/local/bin/opencode2 && opencode --version && opencode2 --version
+ENTRYPOINT ["opencode"]
@@ -0,0 +1,135 @@
+#!/usr/bin/env node
+
+const childProcess = require("child_process")
+const fs = require("fs")
+const path = require("path")
+const os = require("os")
+
+const forwardedSignals =
+  process.platform === "win32" ? ["SIGINT", "SIGTERM", "SIGHUP"] : ["SIGINT", "SIGTERM", "SIGHUP", "SIGUSR1"]
+
+function run(target) {
+  const child = childProcess.spawn(target, process.argv.slice(2), { stdio: "inherit" })
+  child.on("error", (error) => {
+    console.error(error.message)
+    process.exit(1)
+  })
+  const forwarders = {}
+  for (const signal of forwardedSignals) {
+    forwarders[signal] = () => {
+      try {
+        child.kill(signal)
+      } catch {}
+    }
+    process.on(signal, forwarders[signal])
+  }
+  child.on("exit", (code, signal) => {
+    for (const forwardedSignal of forwardedSignals) process.removeListener(forwardedSignal, forwarders[forwardedSignal])
+    if (signal) return process.kill(process.pid, signal)
+    process.exit(typeof code === "number" ? code : 0)
+  })
+}
+
+const envPath = process.env.OPENCODE_BIN_PATH
+const scriptDir = path.dirname(fs.realpathSync(__filename))
+const command = path.basename(__filename).replace(/\.cjs$/, "")
+const nodeBuild = command === "opencode-node"
+const sourceCommand = nodeBuild ? "opencode2-node" : "opencode"
+const cached = path.join(scriptDir, `.${command}`)
+const platform = { darwin: "darwin", linux: "linux", win32: "windows" }[os.platform()] || os.platform()
+const arch = { x64: "x64", arm64: "arm64", arm: "arm" }[os.arch()] || os.arch()
+const base = `@opencode/cli${nodeBuild ? "-node" : ""}-` + platform + "-" + arch
+const binary = platform === "windows" ? `${sourceCommand}.exe` : sourceCommand
+
+function supportsAvx2() {
+  if (arch !== "x64") return false
+  if (platform === "linux") {
+    try {
+      return /(^|\s)avx2(\s|$)/i.test(fs.readFileSync("/proc/cpuinfo", "utf8"))
+    } catch {
+      return false
+    }
+  }
+  if (platform === "darwin") {
+    try {
+      const result = childProcess.spawnSync("sysctl", ["-n", "hw.optional.avx2_0"], { encoding: "utf8", timeout: 1500 })
+      return result.status === 0 && (result.stdout || "").trim() === "1"
+    } catch {
+      return false
+    }
+  }
+  if (platform === "windows") {
+    const command =
+      '(Add-Type -MemberDefinition "[DllImport(""kernel32.dll"")] public static extern bool IsProcessorFeaturePresent(int ProcessorFeature);" -Name Kernel32 -Namespace Win32 -PassThru)::IsProcessorFeaturePresent(40)'
+    for (const executable of ["powershell.exe", "pwsh.exe", "pwsh", "powershell"]) {
+      try {
+        const result = childProcess.spawnSync(executable, ["-NoProfile", "-NonInteractive", "-Command", command], {
+          encoding: "utf8",
+          timeout: 3000,
+          windowsHide: true,
+        })
+        if (result.status !== 0) continue
+        const output = (result.stdout || "").trim().toLowerCase()
+        if (output === "true" || output === "1") return true
+        if (output === "false" || output === "0") return false
+      } catch {
+        continue
+      }
+    }
+  }
+  return false
+}
+
+const names = (() => {
+  if (nodeBuild) return [base]
+  const baseline = arch === "x64" && !supportsAvx2()
+  if (platform === "linux") {
+    const musl = (() => {
+      try {
+        if (fs.existsSync("/etc/alpine-release")) return true
+        const result = childProcess.spawnSync("ldd", ["--version"], { encoding: "utf8" })
+        return ((result.stdout || "") + (result.stderr || "")).toLowerCase().includes("musl")
+      } catch {
+        return false
+      }
+    })()
+    if (musl)
+      return arch === "x64"
+        ? baseline
+          ? [`${base}-baseline-musl`, `${base}-musl`, `${base}-baseline`, base]
+          : [`${base}-musl`, `${base}-baseline-musl`, base, `${base}-baseline`]
+        : [`${base}-musl`, base]
+    return arch === "x64"
+      ? baseline
+        ? [`${base}-baseline`, base, `${base}-baseline-musl`, `${base}-musl`]
+        : [base, `${base}-baseline`, `${base}-musl`, `${base}-baseline-musl`]
+      : [base, `${base}-musl`]
+  }
+  return arch === "x64" ? (baseline ? [`${base}-baseline`, base] : [base, `${base}-baseline`]) : [base]
+})()
+
+function findBinary(startDir) {
+  let current = startDir
+  for (;;) {
+    const modules = path.join(current, "node_modules")
+    if (fs.existsSync(modules))
+      for (const name of names) {
+        const candidate = path.join(modules, name, "bin", binary)
+        if (fs.existsSync(candidate)) return candidate
+      }
+    const parent = path.dirname(current)
+    if (parent === current) return
+    current = parent
+  }
+}
+
+const resolved = envPath || (fs.existsSync(cached) ? cached : findBinary(scriptDir))
+if (!resolved) {
+  console.error(
+    `It seems that your package manager failed to install the right ${command} CLI package. Try manually installing ` +
+      names.map((name) => `"${name}"`).join(" or ") +
+      " package",
+  )
+  process.exit(1)
+}
+run(resolved)
@@ -1,134 +1,3 @@
 #!/usr/bin/env node

-const childProcess = require("child_process")
-const fs = require("fs")
-const path = require("path")
-const os = require("os")
-
-const forwardedSignals =
-  process.platform === "win32" ? ["SIGINT", "SIGTERM", "SIGHUP"] : ["SIGINT", "SIGTERM", "SIGHUP", "SIGUSR1"]
-
-function run(target) {
-  const child = childProcess.spawn(target, process.argv.slice(2), { stdio: "inherit" })
-  child.on("error", (error) => {
-    console.error(error.message)
-    process.exit(1)
-  })
-  const forwarders = {}
-  for (const signal of forwardedSignals) {
-    forwarders[signal] = () => {
-      try {
-        child.kill(signal)
-      } catch {}
-    }
-    process.on(signal, forwarders[signal])
-  }
-  child.on("exit", (code, signal) => {
-    for (const forwardedSignal of forwardedSignals) process.removeListener(forwardedSignal, forwarders[forwardedSignal])
-    if (signal) return process.kill(process.pid, signal)
-    process.exit(typeof code === "number" ? code : 0)
-  })
-}
-
-const envPath = process.env.OPENCODE_BIN_PATH
-const scriptDir = path.dirname(fs.realpathSync(__filename))
-const command = path.basename(__filename).replace(/\.cjs$/, "")
-const nodeBuild = command === "opencode2-node"
-const cached = path.join(scriptDir, `.${command}`)
-const platform = { darwin: "darwin", linux: "linux", win32: "windows" }[os.platform()] || os.platform()
-const arch = { x64: "x64", arm64: "arm64", arm: "arm" }[os.arch()] || os.arch()
-const base = `@opencode/cli${nodeBuild ? "-node" : ""}-` + platform + "-" + arch
-const binary = platform === "windows" ? `${command}.exe` : command
-
-function supportsAvx2() {
-  if (arch !== "x64") return false
-  if (platform === "linux") {
-    try {
-      return /(^|\s)avx2(\s|$)/i.test(fs.readFileSync("/proc/cpuinfo", "utf8"))
-    } catch {
-      return false
-    }
-  }
-  if (platform === "darwin") {
-    try {
-      const result = childProcess.spawnSync("sysctl", ["-n", "hw.optional.avx2_0"], { encoding: "utf8", timeout: 1500 })
-      return result.status === 0 && (result.stdout || "").trim() === "1"
-    } catch {
-      return false
-    }
-  }
-  if (platform === "windows") {
-    const command =
-      '(Add-Type -MemberDefinition "[DllImport(""kernel32.dll"")] public static extern bool IsProcessorFeaturePresent(int ProcessorFeature);" -Name Kernel32 -Namespace Win32 -PassThru)::IsProcessorFeaturePresent(40)'
-    for (const executable of ["powershell.exe", "pwsh.exe", "pwsh", "powershell"]) {
-      try {
-        const result = childProcess.spawnSync(executable, ["-NoProfile", "-NonInteractive", "-Command", command], {
-          encoding: "utf8",
-          timeout: 3000,
-          windowsHide: true,
-        })
-        if (result.status !== 0) continue
-        const output = (result.stdout || "").trim().toLowerCase()
-        if (output === "true" || output === "1") return true
-        if (output === "false" || output === "0") return false
-      } catch {
-        continue
-      }
-    }
-  }
-  return false
-}
-
-const names = (() => {
-  if (nodeBuild) return [base]
-  const baseline = arch === "x64" && !supportsAvx2()
-  if (platform === "linux") {
-    const musl = (() => {
-      try {
-        if (fs.existsSync("/etc/alpine-release")) return true
-        const result = childProcess.spawnSync("ldd", ["--version"], { encoding: "utf8" })
-        return ((result.stdout || "") + (result.stderr || "")).toLowerCase().includes("musl")
-      } catch {
-        return false
-      }
-    })()
-    if (musl)
-      return arch === "x64"
-        ? baseline
-          ? [`${base}-baseline-musl`, `${base}-musl`, `${base}-baseline`, base]
-          : [`${base}-musl`, `${base}-baseline-musl`, base, `${base}-baseline`]
-        : [`${base}-musl`, base]
-    return arch === "x64"
-      ? baseline
-        ? [`${base}-baseline`, base, `${base}-baseline-musl`, `${base}-musl`]
-        : [base, `${base}-baseline`, `${base}-musl`, `${base}-baseline-musl`]
-      : [base, `${base}-musl`]
-  }
-  return arch === "x64" ? (baseline ? [`${base}-baseline`, base] : [base, `${base}-baseline`]) : [base]
-})()
-
-function findBinary(startDir) {
-  let current = startDir
-  for (;;) {
-    const modules = path.join(current, "node_modules")
-    if (fs.existsSync(modules))
-      for (const name of names) {
-        const candidate = path.join(modules, name, "bin", binary)
-        if (fs.existsSync(candidate)) return candidate
-      }
-    const parent = path.dirname(current)
-    if (parent === current) return
-    current = parent
-  }
-}
-
-const resolved = envPath || (fs.existsSync(cached) ? cached : findBinary(scriptDir))
-if (!resolved) {
-  console.error(
-    `It seems that your package manager failed to install the right ${command} CLI package. Try manually installing ` +
-      names.map((name) => `"${name}"`).join(" or ") +
-      " package",
-  )
-  process.exit(1)
-}
-run(resolved)
+require("./opencode.cjs")
@@ -1,10 +1,11 @@
 {
  "$schema": "https://json.schemastore.org/package.json",
  "name": "@opencode/cli",
-  "version": "1.18.4",
+  "version": "2.0.0",
  "type": "module",
  "license": "MIT",
  "bin": {
+    "opencode": "./bin/opencode.cjs",
    "opencode2": "./bin/opencode2.cjs"
  },
  "files": [
@@ -12,7 +12,7 @@ import { verifyArtifact, verifySimulationGraph } from "./verify-artifact"
 import { resolveOpencodePty } from "./opencode-pty"

 const dir = path.resolve(import.meta.dirname, "..")
-const binary = "opencode2"
+const binary = "opencode"
 const outdir = path.resolve(
  dir,
  process.argv.find((arg) => arg.startsWith("--outdir="))?.slice("--outdir=".length) ?? "dist",
@@ -149,7 +149,7 @@ export default { path: file, version: ${JSON.stringify(opencodePty.version)}, sh
    },
    define: {
      OPENCODE_VERSION: `'${Script.version}'`,
-      OPENCODE_CLI_NAME: `'${binary}'`,
+      OPENCODE_CLI_NAME: "'opencode'",
      OPENCODE_CHANNEL: `'${Script.channel}'`,
      OPENCODE_ARTIFACT: `'cli'`,
      OPENCODE_LIBC: item.os === "linux" ? `'${item.abi ?? "glibc"}'` : "undefined",
@@ -12,10 +12,11 @@ const require = createRequire(import.meta.url)
 const packageJson = JSON.parse(fs.readFileSync(path.join(directory, "package.json"), "utf8"))
 const command = Object.keys(packageJson.bin ?? {})[0]
 if (!command) throw new Error("OpenCode package does not declare a binary")
+const sourceCommand = packageJson.opencodeSourceBinary ?? command

 const platform = { darwin: "darwin", linux: "linux", win32: "windows" }[os.platform()] ?? os.platform()
 const arch = { x64: "x64", arm64: "arm64", arm: "arm" }[os.arch()] ?? os.arch()
-const sourceBinary = platform === "windows" ? `${command}.exe` : command
+const sourceBinary = platform === "windows" ? `${sourceCommand}.exe` : sourceCommand
 const targetBinary = path.resolve(directory, packageJson.bin[command])
 const dependencies = packageJson.optionalDependencies ?? {}
 const base = Object.keys(dependencies).find((name) => name.endsWith(`-${platform}-${arch}`))
@@ -6,15 +6,10 @@ import path from "node:path"
 import { fileURLToPath } from "node:url"
 import { UpdateArtifact } from "../../../script/update-artifact"

-if (Script.channel !== "beta" && Script.channel !== "latest") {
-  throw new Error("AUR publishing requires the beta or latest channel")
-}
-const beta = Script.channel === "beta"
-const name = beta ? "opencode-beta" : "opencode-bin"
-const command = beta ? "opencode2" : "opencode"
-if (!(beta ? /^\d+\.\d+\.\d+-beta[.-]\d+(?:\.\d+)?$/ : /^\d+\.\d+\.\d+$/).test(Script.version)) {
-  throw new Error(`Expected a ${Script.channel} release version`)
-}
+if (Script.channel !== "beta") throw new Error("AUR publishing requires the beta channel")
+const name = "opencode-beta"
+const command = "opencode"
+if (!/^\d+\.\d+\.\d+-beta[.-]\d+(?:\.\d+)?$/.test(Script.version)) throw new Error("Expected a beta release version")

 const dir = fileURLToPath(new URL("..", import.meta.url))
 const root = path.resolve(process.env.OPENCODE_CLI_DIST ?? path.join(dir, "dist"))
@@ -22,6 +17,9 @@ const outdir = path.join(root, `aur-${name}`)
 const dryRun = process.argv.includes("--dry-run")
 const pkgver = Script.version.replaceAll("-", ".")
 const license = Bun.file(path.join(dir, "..", "..", "LICENSE"))
+const shim = `#!/bin/sh
+exec "$(dirname "$0")/opencode" "$@"
+`

 await rm(outdir, { recursive: true, force: true })
 await mkdir(path.dirname(outdir), { recursive: true })
@@ -48,6 +46,7 @@ const sources = await Promise.all(
 )

 await Bun.write(path.join(outdir, "LICENSE"), license)
+await Bun.write(path.join(outdir, "opencode2"), shim)
 await Bun.write(
  path.join(outdir, "PKGBUILD"),
  [
@@ -55,21 +54,22 @@ await Bun.write(
    `pkgname=${name}`,
    `pkgver=${pkgver}`,
    "pkgrel=1",
-    `pkgdesc='OpenCode${beta ? " V2 beta" : ""} - the AI coding agent for the terminal'`,
+    "pkgdesc='OpenCode beta - the AI coding agent for the terminal'",
    "url='https://github.com/anomalyco/opencode'",
    "arch=('x86_64' 'aarch64')",
    "license=('MIT')",
    "depends=('glibc' 'gcc-libs' 'ripgrep')",
-    `provides=('${command}')`,
-    `conflicts=('${command}')`,
+    `provides=('${command}' 'opencode2')`,
+    `conflicts=('${command}' 'opencode2')`,
    // Stripping a compiled Bun executable can damage its embedded application.
    "options=('!strip' '!debug')",
-    "source=('LICENSE')",
-    `sha256sums=('${new Bun.CryptoHasher("sha256").update(await license.arrayBuffer()).digest("hex")}')`,
+    "source=('LICENSE' 'opencode2')",
+    `sha256sums=('${new Bun.CryptoHasher("sha256").update(await license.arrayBuffer()).digest("hex")}' '${new Bun.CryptoHasher("sha256").update(shim).digest("hex")}')`,
    ...sources,
    "",
    "package() {",
-    `  install -Dm755 "$srcdir/package/bin/opencode2" "$pkgdir/usr/bin/${command}"`,
+    `  install -Dm755 "$srcdir/package/bin/opencode" "$pkgdir/usr/bin/${command}"`,
+    '  install -Dm755 "$srcdir/opencode2" "$pkgdir/usr/bin/opencode2"',
    '  install -Dm644 "$srcdir/LICENSE" "$pkgdir/usr/share/licenses/$pkgname/LICENSE"',
    "}",
    "",
@@ -79,7 +79,7 @@ await Bun.write(path.join(outdir, ".SRCINFO"), await $`makepkg --printsrcinfo`.c
 console.log(`Prepared ${name} ${pkgver} in ${outdir}`)
 if (dryRun) process.exit(0)

-await $`git add PKGBUILD .SRCINFO LICENSE`.cwd(outdir)
+await $`git add PKGBUILD .SRCINFO LICENSE opencode2`.cwd(outdir)
 if ((await $`git diff --cached --quiet`.cwd(outdir).nothrow()).exitCode !== 0) {
  await $`git commit -m ${`chore: update ${name} to ${pkgver}`}`.cwd(outdir)
  await $`git push origin master`.cwd(outdir)
@@ -29,6 +29,8 @@ async function publish(dir: string, name: string, version: string) {
 async function publishDistribution(input: {
  root: string
  name: string
+  command: string
+  legacyCommand?: string
  binary: string
  packagePrefix: string
  artifact: string
@@ -48,7 +50,7 @@ async function publishDistribution(input: {

  await $`mkdir -p ${input.root}/${input.name}/bin`
  await $`cp ./script/postinstall.mjs ${input.root}/${input.name}/postinstall.mjs`
-  await Bun.file(`${input.root}/${input.name}/bin/${input.binary}.exe`).write(
+  await Bun.file(`${input.root}/${input.name}/bin/${input.command}.exe`).write(
    [
      `echo "Error: ${input.name}'s postinstall script was not run." >&2`,
      'echo "" >&2',
@@ -62,7 +64,11 @@ async function publishDistribution(input: {
    JSON.stringify(
      {
        name: input.name,
-        bin: { [input.binary]: `./bin/${input.binary}.exe` },
+        bin: {
+          [input.command]: `./bin/${input.command}.exe`,
+          ...(input.legacyCommand ? { [input.legacyCommand]: `./bin/${input.command}.exe` } : {}),
+        },
+        ...(input.command !== input.binary ? { opencodeSourceBinary: input.binary } : {}),
        scripts: { postinstall: "node ./postinstall.mjs" },
        version,
        license: pkg.license,
@@ -120,21 +126,28 @@ async function publishDistribution(input: {
 await publishDistribution({
  root,
  name: pkg.name,
-  binary: "opencode2",
+  command: "opencode",
+  legacyCommand: "opencode2",
+  binary: "opencode",
  packagePrefix: "@opencode/cli-",
  artifact: "cli",
 })
-if (existsSync(path.join(root, "node"))) {
+if (Script.channel !== "latest" && existsSync(path.join(root, "node"))) {
  await publishDistribution({
    root: path.join(root, "node"),
    name: "@opencode/cli-node",
+    command: "opencode2-node",
    binary: "opencode2-node",
    packagePrefix: "@opencode/cli-node-",
    artifact: "cli-node",
  })
 }

-if ((Script.channel === "beta" || Script.channel === "latest") && Script.release) {
+if (Script.channel === "latest" && Script.release && !dryRun) {
+  await $`docker buildx build --platform linux/amd64,linux/arm64 --tag ghcr.io/anomalyco/opencode:${Script.version} --push .`
+}
+
+if (Script.channel === "beta" && Script.release) {
  await $`bun ./script/publish-aur.ts ${dryRun ? ["--dry-run"] : []}`.env({ ...process.env, OPENCODE_CLI_DIST: root })
 }

@@ -11,7 +11,10 @@ import path from "node:path"
 const nodeBuild = process.argv.includes("--node")
 const target = `cli${nodeBuild ? "-node" : ""}-${process.platform === "win32" ? "windows" : process.platform}-${process.arch}`
 const directory = path.join(import.meta.dir, "..", "dist", ...(nodeBuild ? ["node"] : []), target, "bin")
-const binary = path.join(directory, `opencode2${nodeBuild ? "-node" : ""}${process.platform === "win32" ? ".exe" : ""}`)
+const binary = path.join(
+  directory,
+  `${nodeBuild ? "opencode2-node" : "opencode"}${process.platform === "win32" ? ".exe" : ""}`,
+)
 if (!(await Bun.file(binary).exists())) throw new Error(`Missing compiled CLI in ${directory}`)

 const root = await fs.realpath(await fs.mkdtemp(path.join(os.tmpdir(), "opencode-service-smoke-")))
@@ -36,7 +36,7 @@ const PermissionParams = {
 }

 const Root = Spec.make(typeof OPENCODE_CLI_NAME === "string" ? OPENCODE_CLI_NAME : "opencode", {
-  description: "OpenCode 2.0 preview command line interface",
+  description: "OpenCode command line interface",
  params: {
    ...ServerParams,
    ...PermissionParams,
@@ -105,7 +105,7 @@ const make = Effect.gen(function* () {
      global.home,
      ".opencode",
      "bin",
-      process.platform === "win32" ? "opencode2.exe" : "opencode2",
+      process.platform === "win32" ? "opencode.exe" : "opencode",
    )
    if (path.resolve(process.execPath) === path.resolve(binary)) return "curl"
    if (!installedPackage) return
@@ -186,7 +186,10 @@ const make = Effect.gen(function* () {
        "npm",
        "install",
        "--global",
-        ...(installedPackage && packageName !== installedPackage ? ["--force"] : []),
+        ...((OPENCODE_ARTIFACT === "cli" && !installedPackage?.endsWith("/cli-node")) ||
+        (installedPackage && packageName !== installedPackage)
+          ? ["--force"]
+          : []),
        target,
      ],
      pnpm: ["pnpm", "add", "--global", `--allow-build=${packageName}`, target],
@@ -423,24 +423,24 @@ test("updates effective duplicate canonical keybinds", async () => {
  const file = path.join(directory.path, "cli.json")
  await Bun.write(
    file,
-    `{"keybinds":{"session.delete":"first","session.delete":"last","permission.mode":"off","permission.mode":"on"}}`,
+    `{"keybinds":{"session.delete":"first","session.delete":"last","opencode.settings":"off","opencode.settings":"on"}}`,
  )

  const config = await run(
    directory.path,
    Effect.gen(function* () {
      const service = yield* Config.Service
-      expect((yield* service.get()).keybinds).toEqual({ "session.delete": "last", "permission.mode": "on" })
+      expect((yield* service.get()).keybinds).toEqual({ "session.delete": "last", "opencode.settings": "on" })
      return yield* service.update((draft) => {
-        draft.keybinds = { ...draft.keybinds, "session.delete": "changed", "permission.mode": "changed" }
+        draft.keybinds = { ...draft.keybinds, "session.delete": "changed", "opencode.settings": "changed" }
      })
    }),
  )

-  expect(config.keybinds).toEqual({ "session.delete": "changed", "permission.mode": "changed" })
+  expect(config.keybinds).toEqual({ "session.delete": "changed", "opencode.settings": "changed" })
  expect(parse(await Bun.file(file).text()).keybinds).toEqual({
    "session.delete": "changed",
-    "permission.mode": "changed",
+    "opencode.settings": "changed",
  })
 })

@@ -100,7 +100,7 @@ function fixture(
 }

 const installs = [
-  { method: "npm", command: ["npm", "install", "--global", "@opencode/cli@2.3.4-beta.1"] },
+  { method: "npm", command: ["npm", "install", "--global", "--force", "@opencode/cli@2.3.4-beta.1"] },
  {
    method: "pnpm",
    command: ["pnpm", "add", "--global", "--allow-build=@opencode/cli", "@opencode/cli@2.3.4-beta.1"],
@@ -1,7 +1,7 @@
 {
  "$schema": "https://json.schemastore.org/package.json",
  "name": "@opencode/client",
-  "version": "1.17.13",
+  "version": "2.0.0",
  "type": "module",
  "license": "MIT",
  "repository": {
@@ -9,7 +9,8 @@ standard-library surface that programs can use today, plus concrete gaps that ma
 - Intentional boundaries are not listed as compatibility work.

 When behavior changes, update this file and the tests in the same change. The implementation and tests remain the
-ultimate source of truth.
+ultimate source of truth. Upstream test262 files run verbatim from `test/test262`; a failing file is listed in
+`test/test262/skipped.txt` and its gap is an unchecked item here (see `test/test262/README.md`).

 ## Source and execution model

@@ -25,6 +26,10 @@ ultimate source of truth.
 - [x] The global `search(...)` built-in: synchronous tool discovery that counts as an admitted tool call and is
      shadowable by program declarations like other globals.
 - [x] Cooperative timeout, an optional total tool-call limit, output bounding, and unrestricted tool-call concurrency.
+- [ ] Strict-mode early errors: duplicate parameter names, `yield` as an identifier, and a trailing comma after a
+      rest parameter are accepted unless the program itself begins with `"use strict"`.
+- [ ] Valid JavaScript rejected by TypeScript transpilation before interpretation, such as `in` inside a destructuring
+      default in a `for...of` head and Unicode-escaped keywords.

 ## Values and literals

@@ -64,6 +69,11 @@ ultimate source of truth.
 - [x] Array binding and assignment destructuring from strings, Maps, Sets, URLSearchParams, custom synchronous
      iterators, and synchronous generators, including stepwise elisions/rest and `IteratorClose` on early completion
      or binding/default failure.
+- [ ] Object destructuring from primitives follows ToObject (`const { length } = "abc"`, `const {} = 1`); non-object
+      sources are rejected.
+- [ ] Destructuring a key that member access resolves through the owning built-in, such as
+      `const { constructor } = error`, reads `undefined`.
+- [ ] Member expressions as `for...in` targets (`for (x.y in obj)`).

 ## Statements and control flow

@@ -111,6 +121,15 @@ ultimate source of truth.
 - [ ] User-defined constructor calls.
 - [ ] `Function.prototype.call`, `apply`, and `bind` for CodeMode functions.
 - [ ] Classes and private fields.
+- [x] Functions are objects: they hold own properties (`fn.count = 1`), enumerate them, and expose read-only `name`
+      and `length`. Names follow JavaScript's NamedEvaluation: declarations, named expressions, bindings,
+      assignments, object literal keys, and destructuring or parameter defaults.
+- [ ] `name` and `length` of built-in functions such as `Math.max` or `"a".includes`.
+- [ ] A named function expression's name is not bound inside its own body.
+- [ ] Redeclaring a function in the same scope is rejected; in JavaScript the last declaration wins.
+- [ ] A line terminator between `async function` and the function name.
+- [ ] Async generator functions evaluate parameter defaults and destructuring at the first `next()` rather than at the
+      call, so their errors are not thrown synchronously.
 - [x] Synchronous and async generator declarations/expressions, `yield`, and `yield*`, including lazy bodies,
      `next(value)`, `return(value)`, `throw(value)`, exhaustion, promise adoption, async request ordering,
      `try`/`catch`/`finally`, and sync/async iterator symbols. Async `yield*` awaits values while adapting a sync
@@ -154,6 +173,8 @@ ultimate source of truth.
 - [x] Plain, arithmetic, bitwise, and logical assignment operators.
 - [x] Property deletion on plain data objects and arrays, including computed and optional forms; deleting an array index
      creates a hole without changing its length.
+- [ ] Operators, `switch` discriminants, and coercion helpers such as `String` and `isNaN` applied to functions and
+      namespaces; JavaScript coerces them, the interpreter rejects non-data operands.

 ## Promises and tools

@@ -225,7 +246,8 @@ ultimate source of truth.
 - [x] Circular references are rejected when created (`o.self = o`, `array.push(array)`), not at serialization as in JS.
 - [x] `Object.is` for supported data values.
 - [x] `Object.groupBy` over finite collections and custom synchronous iterators/generators, with string-key coercion
-      and null-prototype results.
+      and plain-object results.
+- [ ] `Object.prototype` methods on values: `toString`, `toLocaleString`, `valueOf`, and `hasOwnProperty`.

 ## Arrays

@@ -245,10 +267,18 @@ ultimate source of truth.
 - [x] `length`, numeric indexing, index assignment, spread, and `for...of`.
 - [x] The `thisArg` argument of `Array.from` is accepted and ignored, like JS arrows.
 - [x] `Array.prototype.toSpliced`.
- [x] Canonical array/string index parsing: keys such as `"01"` remain non-index properties rather than aliasing index
-      `1`; arbitrary array-property assignment remains unsupported.
+- [x] Canonical array/string index parsing: keys such as `"01"` are ordinary properties rather than aliases of index
+      `1`.
 - [x] `Array.prototype.sort` preserves trailing holes, while `toSorted` densifies holes into `undefined` elements,
      like JavaScript.
+- [x] Assigning `length` to truncate or extend an array; invalid lengths throw `RangeError`.
+- [x] Non-index own properties on arrays (`arr.foo = 1`, `arr.constructor = null`). They are excluded from the JSON
+      form, like `JSON.stringify`.
+- [ ] Argument coercion for `indexOf`, `lastIndexOf`, `includes`, `fill`, `flat`, `copyWithin`, and the `join`
+      separator: JavaScript applies ToIntegerOrInfinity/ToString (including `valueOf`, strings, and `undefined`), the
+      interpreter requires numbers and strings; `includes()`/`indexOf()` with no argument should search for
+      `undefined`.
+- [ ] Iterator objects from `keys`, `values`, and `entries` with a live `next()`.

 ## Strings

@@ -332,7 +362,7 @@ ultimate source of truth.
 - [x] `test`, `exec`, and `toString`.
 - [x] Readable `source`, `flags`, `lastIndex`, `hasIndices`, `global`, `ignoreCase`, `multiline`, `sticky`, `unicode`,
      `unicodeSets`, and `dotAll`.
- [x] Captures, named groups, match `.index`, and stateful global matching.
+- [x] Captures, named groups, match `.index` and `.input`, and stateful global matching.
 - [x] Integration with supported String methods, including function replacers.
 - [x] Writable `lastIndex`.
 - [x] Match `indices` metadata for the `d` flag, including named groups on `exec`, `match`, and `matchAll` results.
@@ -391,3 +421,5 @@ ultimate source of truth.
 - [x] Caught errors do not distinguish user throws, interpreter failures, and tool failures; a program sees one
      Error-shaped value with `name` and `message` in `catch`, rejection handlers, and `Promise.allSettled` reasons.
      This is deliberate: the program should handle a failure the same way regardless of where it originated.
+- [ ] Failures raised by the interpreter itself carry the generic `Error` name where JavaScript throws a `TypeError`,
+      `RangeError`, or `ReferenceError`, so `e instanceof TypeError` and `e.constructor === TypeError` are false.
@@ -1,7 +1,7 @@
 {
  "$schema": "https://json.schemastore.org/package.json",
  "name": "@opencode/codemode",
-  "version": "1.18.4",
+  "version": "2.0.0",
  "description": "Effect-native confined code execution over schema-described tools",
  "type": "module",
  "license": "MIT",
@@ -0,0 +1,62 @@
+// Copies the manifest's test262 directories from a local checkout into test/test262, verbatim.
+// Files needing unsupported flags, features, or harness includes, or whose code crosses one of the
+// interpreter's intentional boundaries, are not copied, so the vendored tree is exactly what
+// test/test262.test.ts runs.
+//
+// Usage: bun run script/sync-test262.ts /path/to/test262
+import path from "node:path"
+import { rm } from "node:fs/promises"
+
+type Frontmatter = { flags?: Array<string>; features?: Array<string>; includes?: Array<string> }
+
+const root = path.resolve(import.meta.dir, "../test/test262")
+const manifest = (await Bun.file(path.join(root, "manifest.json")).json()) as {
+  revision: string
+  directories: Array<string>
+  harness: Array<string>
+  flags: Array<string>
+  features: Array<string>
+  boundaries: Record<string, string>
+}
+const boundaries = Object.entries(manifest.boundaries).map(([name, pattern]) => [name, new RegExp(pattern)] as const)
+const checkout = process.argv[2]
+if (checkout === undefined) {
+  console.error("usage: bun run script/sync-test262.ts /path/to/test262")
+  process.exit(1)
+}
+const head = (await Bun.$`git -C ${checkout} rev-parse HEAD`.text()).trim()
+if (head !== manifest.revision) {
+  console.error(`checkout is at ${head}; manifest pins ${manifest.revision}`)
+  process.exit(1)
+}
+
+const excluded = new Map<string, number>()
+let copied = 0
+for (const dir of manifest.directories) {
+  await rm(path.join(root, dir), { recursive: true, force: true })
+  const from = path.join(checkout, "test", dir)
+  for await (const file of new Bun.Glob("**/*.js").scan({ cwd: from })) {
+    if (file.endsWith("_FIXTURE.js")) continue
+    const source = await Bun.file(path.join(from, file)).text()
+    const start = source.indexOf("/*---")
+    const end = source.indexOf("---*/", start)
+    const meta = start === -1 ? {} : (Bun.YAML.parse(source.slice(start + 5, end)) as Frontmatter)
+    const code = start === -1 ? source : source.slice(end + 5)
+    const reason =
+      meta.flags?.find((flag) => manifest.flags.includes(flag)) ??
+      meta.features?.find((feature) => manifest.features.includes(feature)) ??
+      meta.includes?.find((include) => !manifest.harness.includes(include)) ??
+      boundaries.find(([, pattern]) => pattern.test(code))?.[0]
+    if (reason !== undefined) {
+      excluded.set(reason, (excluded.get(reason) ?? 0) + 1)
+      continue
+    }
+    await Bun.write(path.join(root, dir, file), Bun.file(path.join(from, file)))
+    copied++
+  }
+}
+
+console.log(`copied ${copied} files`)
+for (const [reason, count] of [...excluded].sort((a, b) => b[1] - a[1])) {
+  console.log(`  excluded ${String(count).padStart(5)}  ${reason}`)
+}
@@ -0,0 +1,55 @@
+// Runs every vendored test262 file, including skipped ones, and groups failures by cause. Pass
+// --write to regenerate test/test262/skipped.txt from the current failures.
+//
+// Usage: bun run script/test262-report.ts [--write] [path-prefix]
+import path from "node:path"
+import { root, run, skipped } from "../test/test262/run.js"
+
+const write = process.argv.includes("--write")
+const prefix = process.argv.slice(2).find((arg) => !arg.startsWith("--")) ?? ""
+const files = [...new Bun.Glob("**/*.js").scanSync({ cwd: root })].filter((file) => file.startsWith(prefix)).sort()
+
+const failures: Array<{ file: string; reason: string }> = []
+const recovered: Array<string> = []
+for (const file of files) {
+  const outcome = await run(file)
+  if (outcome.status === "fail") failures.push({ file, reason: outcome.reason })
+  if (outcome.status === "pass" && skipped.has(file)) recovered.push(file)
+}
+
+// Collapse a reason to the part that identifies the cause rather than the test.
+const bucket = (reason: string) => {
+  const syntax = reason.match(/Syntax '([A-Za-z]+)' is not supported/)
+  if (syntax) return `unsupported syntax ${syntax[1]}`
+  if (reason.startsWith("expected ")) return reason.replace(/ but got .*/, " but the program ran")
+  return reason
+    .replace(/^(\$DONE: |ExecutionFailure: |InvalidDataValue: |ParseError: |Uncaught: |Test262Error: |Error: )+/, "")
+    .replace(/ \(line \d+, col \d+\)/, "")
+    .replace(/^[\w$]+\.(\w+) is not a function/, ".$1 is not a function")
+    .replace(/^[\w$]+ cannot be constructed/, "… cannot be constructed")
+    .replace(/'[^']*'/g, "'…'")
+    .slice(0, 100)
+}
+
+const buckets = new Map<string, Array<string>>()
+for (const failure of failures) {
+  const key = bucket(failure.reason)
+  buckets.set(key, [...(buckets.get(key) ?? []), failure.file])
+}
+
+console.log(`${files.length - failures.length} pass, ${failures.length} fail of ${files.length}\n`)
+for (const [key, list] of [...buckets].sort((a, b) => b[1].length - a[1].length)) {
+  console.log(`${String(list.length).padStart(5)}  ${key}`)
+  for (const file of list.slice(0, 3)) console.log(`         ${file}`)
+  if (list.length > 3) console.log(`         … ${list.length - 3} more`)
+}
+if (recovered.length > 0) {
+  console.log(`\n${recovered.length} skipped files pass now; remove them from skipped.txt:`)
+  for (const file of recovered) console.log(`         ${file}`)
+}
+
+if (write) {
+  const lines = failures.map((failure) => `${failure.file}  # ${bucket(failure.reason)}`)
+  await Bun.write(path.join(root, "skipped.txt"), `${lines.join("\n")}\n`)
+  console.log(`\nwrote ${lines.length} entries to skipped.txt`)
+}
@@ -1,11 +1,16 @@
 export * as Data from "./data.js"

 import type { DiagnosticKind } from "./codemode.js"
+import {
+  ownEntries,
+  parseArrayIndex,
+  ProgramArray,
+  ProgramFunction,
+  ProgramObject,
+  set,
+} from "./interpreter/objects.js"
 import { Values } from "./values.js"

-/** A null-prototype object owned by the program. */
-export type SafeObject = Record<string, unknown>
-
 const MAX_VALUE_DEPTH = 32

 export class ToolRuntimeError extends Error {
@@ -23,15 +28,15 @@ export class ToolRuntimeError extends Error {
 }

 /**
- * Brings a host-produced runtime value into the program: runtime values pass through, their host
- * counterparts (Date, RegExp, Map, Set, URL, URLSearchParams) are wrapped, and objects become
- * null-prototype copies. Arrays keep extra enumerable properties such as `index` and `groups`.
+ * Brings a host-produced value into the program: program and runtime values pass through, their
+ * host counterparts (Date, RegExp, Map, Set, URL, URLSearchParams) are wrapped, and host objects
+ * and arrays are copied.
 */
 export const toProgram = (value: unknown, label: string): unknown => copy(value, label, "program", 0, new Set())

 /**
 * Brings host data into the program: Date and URL become strings, other host collections become
- * empty objects, and objects become null-prototype copies. Used for tool results and parsed JSON.
+ * empty objects, and objects become program copies. Used for tool results and parsed JSON.
 */
 export const fromData = (value: unknown, label: string): unknown => copy(value, label, "data", 0, new Set())

@@ -44,8 +49,7 @@ export const fromData = (value: unknown, label: string): unknown => copy(value,
 export const toData = (value: unknown, label: string, undefinedAs: "json" | "result" = "json"): unknown =>
  copy(value, label, undefinedAs, 0, new Set())

-// "program" and "data" build program-owned null-prototype objects; "json" and "result" build
-// ordinary objects for the host.
+// "program" and "data" build program objects; "json" and "result" build ordinary objects for the host.
 type Mode = "program" | "data" | "json" | "result"

 const copy = (value: unknown, label: string, mode: Mode, depth: number, seen: Set<object>): unknown => {
@@ -64,9 +68,13 @@ const copy = (value: unknown, label: string, mode: Mode, depth: number, seen: Se
      `${label} contains an un-awaited Promise; await tool calls (e.g. \`const result = await tools.ns.tool(...)\`) before using their results.`,
    )
  }
+  if (value instanceof ProgramFunction && mode !== "program") {
+    throw new ToolRuntimeError("InvalidDataValue", `${label} must contain data only.`)
+  }

+  const plain = mode === "program" || mode === "data"
  if (mode === "program") {
-    if (Values.isValue(value)) return value
+    if (value instanceof ProgramObject || Values.isValue(value)) return value
    if (value instanceof Date) return new Values.Date(value.getTime())
    if (value instanceof RegExp) return new Values.RegExp(value.source, value.flags)
    if (value instanceof Map) {
@@ -85,7 +93,6 @@ const copy = (value: unknown, label: string, mode: Mode, depth: number, seen: Se
    if (value instanceof URLSearchParams) return new Values.URLSearchParams(new URLSearchParams(value))
  }

-  const plain = mode === "program" || mode === "data"
  if (value instanceof Values.Date) return Number.isFinite(value.time) ? new Date(value.time).toISOString() : null
  if (value instanceof Date) return Number.isFinite(value.getTime()) ? value.toISOString() : null
  if (value instanceof Values.URL) return value.url.href
@@ -98,7 +105,7 @@ const copy = (value: unknown, label: string, mode: Mode, depth: number, seen: Se
    value instanceof Set ||
    value instanceof URLSearchParams
  ) {
-    return plain ? (Object.create(null) as SafeObject) : {}
+    return plain ? new ProgramObject() : {}
  }

  if (seen.has(value)) {
@@ -106,27 +113,48 @@ const copy = (value: unknown, label: string, mode: Mode, depth: number, seen: Se
  }
  seen.add(value)

-  if (Array.isArray(value)) {
-    // Host output densifies holes to null like JSON; program copies keep them.
-    const copied = plain
-      ? value.map((item) => copy(item, label, mode, depth + 1, seen))
-      : Array.from(value, (item) => copy(item, label, mode, depth + 1, seen) ?? null)
-    if (mode === "program") {
-      for (const [key, item] of Object.entries(value)) {
-        if (Object.hasOwn(copied, key)) continue
-        define(copied, key, copy(item, label, mode, depth + 1, seen))
-      }
+  if (value instanceof ProgramArray) {
+    const copied = Array.from(value.items, (item) => copy(item, label, mode, depth + 1, seen) ?? null)
+    seen.delete(value)
+    return copied
+  }
+  if (value instanceof ProgramObject) {
+    const copied: Record<string, unknown> = {}
+    for (const [key, item] of ownEntries(value)) {
+      const next = copy(item, label, mode, depth + 1, seen)
+      if (next === undefined && mode === "json") continue
+      define(copied, key, next)
    }
    seen.delete(value)
    return copied
  }

+  if (Array.isArray(value)) {
+    if (plain) {
+      const copied = new ProgramArray(value.map((item) => copy(item, label, mode, depth + 1, seen)))
+      for (const [key, item] of Object.entries(value)) {
+        if (parseArrayIndex(key) === undefined) set(copied, key, copy(item, label, mode, depth + 1, seen))
+      }
+      seen.delete(value)
+      return copied
+    }
+    const copied = Array.from(value, (item) => copy(item, label, mode, depth + 1, seen) ?? null)
+    seen.delete(value)
+    return copied
+  }
+
  const prototype = Object.getPrototypeOf(value)
  if (prototype !== Object.prototype && prototype !== null) {
    throw new ToolRuntimeError("InvalidDataValue", `${label} must contain plain objects only.`)
  }

-  const copied: SafeObject = plain ? (Object.create(null) as SafeObject) : {}
+  if (plain) {
+    const copied = new ProgramObject()
+    for (const [key, item] of Object.entries(value)) set(copied, key, copy(item, label, mode, depth + 1, seen))
+    seen.delete(value)
+    return copied
+  }
+  const copied: Record<string, unknown> = {}
  for (const [key, item] of Object.entries(value)) {
    const next = copy(item, label, mode, depth + 1, seen)
    if (next === undefined && mode === "json") continue
@@ -136,8 +164,8 @@ const copy = (value: unknown, label: string, mode: Mode, depth: number, seen: Se
  return copied
 }

-// Own data property regardless of the target's prototype, so a "__proto__" key on a host object or
-// array never reaches the Object.prototype setter.
+// Own data property regardless of the target's prototype, so a "__proto__" key on a host object
+// never reaches the Object.prototype setter.
 const define = (target: object, key: string, value: unknown): void => {
  Object.defineProperty(target, key, { value, enumerable: true, writable: true, configurable: true })
 }
@@ -1,10 +1,11 @@
 import { Effect } from "effect"
 import type { Diagnostic } from "../codemode.js"
 import { ToolError } from "../tool-error.js"
-import { type SafeObject, toData, ToolRuntimeError } from "../data.js"
+import { toData, ToolRuntimeError } from "../data.js"
 import { type AstNode, formatLocation, InterpreterRuntimeError, ProgramThrow, sourceLocation } from "./model.js"
 import { containsRuntimeReference } from "./references.js"
 import { type HostCall, HostFunction } from "./host.js"
+import { get, ProgramError, ProgramObject } from "./objects.js"
 import { type Runner } from "./runner.js"
 import {
  coerceToString,
@@ -44,12 +45,8 @@ export const normalizeError = (error: unknown): Diagnostic => {
      message = "a non-data value"
    } else if (typeof value === "string") {
      message = value
-    } else if (
-      value !== null &&
-      typeof value === "object" &&
-      typeof (value as { message?: unknown }).message === "string"
-    ) {
-      message = (value as { message: string }).message
+    } else if (value instanceof ProgramObject && typeof get(value, "message") === "string") {
+      message = get(value, "message") as string
    } else {
      try {
        message = JSON.stringify(toData(value, "Thrown value")) ?? String(value)
@@ -87,14 +84,14 @@ export const caughtErrorValue = (thrown: unknown): unknown => {
  return createErrorValue(name, normalizeError(thrown).message)
 }

-const constructErrorValue = (name: string, args: Array<unknown>): SafeObject =>
+const constructErrorValue = (name: string, args: Array<unknown>): ProgramError =>
  createErrorValue(name, args[0] === undefined ? "" : coerceToString(args[0]))

 const constructAggregateErrorValue = <R>(
  runner: Runner<R>,
  args: Array<unknown>,
  node: AstNode,
-): Effect.Effect<SafeObject, unknown, R> =>
+): Effect.Effect<ProgramError, unknown, R> =>
  Effect.gen(function* () {
    const cursor = yield* runner.syncIterator(args[0], node)
    if (cursor === undefined) {
@@ -7,6 +7,7 @@ import type { DataValue, Diagnostic, ResolvedExecutionLimits, Result } from "../
 import { toData } from "../data.js"
 import { ToolRuntime } from "../tool-runtime.js"
 import { normalizeError } from "./errors.js"
+import type { Host } from "./globals.js"
 import { InterpreterRuntimeError } from "./model.js"
 import { PromiseRuntime } from "./promises.js"
 import { Runtime } from "./runtime.js"
@@ -16,6 +17,7 @@ export const executeProgram = <R>(
  prepared: ToolRuntime.Prepared<R>,
  limits: ResolvedExecutionLimits,
  hooks: ToolRuntime.ToolCallHooks<R>,
+  extraGlobals?: (host: Host<R>) => ReadonlyArray<readonly [string, unknown]>,
 ): Effect.Effect<Result, never, R> => {
  if (code.trim().length === 0) {
    return Effect.succeed({
@@ -39,7 +41,14 @@ export const executeProgram = <R>(
        Effect.gen(function* () {
          const program = parseProgram(code)
          const promises = new PromiseRuntime<R>(scope)
-          const value = yield* new Runtime<R>(tools.execute, tools.search, tools.keys, promises, logs).run(program)
+          const value = yield* new Runtime<R>(
+            tools.execute,
+            tools.search,
+            tools.keys,
+            promises,
+            logs,
+            extraGlobals,
+          ).run(program)
          const result = toData(value, "Execution result", "result") as DataValue
          returned = { value: result, promises }
          const warnings = yield* promises.interrupt()
@@ -1,13 +1,14 @@
 import { Effect } from "effect"
-import { type SafeObject, toProgram } from "../data.js"
+import { toProgram } from "../data.js"
 import { dateSetterArgumentCount, invokeDateMethod } from "../stdlib/date.js"
 import { invokeNumberMethod } from "../stdlib/number.js"
 import { invokeRegExpMethod, matchToValue, toHostRegex } from "../stdlib/regexp.js"
 import { invokeURLMethod, uriArgument } from "../stdlib/url.js"
-import { coerceToNumber, coerceToString, errorBrandName } from "../stdlib/value.js"
+import { coerceToNumber, coerceToString } from "../stdlib/value.js"
 import { compareText } from "../tool-runtime.js"
 import { Values } from "../values.js"
 import { type AstNode, IntrinsicReference, InterpreterRuntimeError } from "./model.js"
+import { get, ProgramArray, ProgramObject, record } from "./objects.js"
 import { containsOpaqueReference, rejectCircularInsertion, typeofValue } from "./references.js"
 import { applyCollectionCallback, isSupportedCallback, type Runner, toPrimitive } from "./runner.js"

@@ -16,6 +17,14 @@ export const invokeIntrinsic = <R>(
  ref: IntrinsicReference,
  args: Array<unknown>,
  node: AstNode,
+): Effect.Effect<unknown, unknown, R> =>
+  Effect.map(invoke(runner, ref, args, node), (result) => (Array.isArray(result) ? new ProgramArray(result) : result))
+
+const invoke = <R>(
+  runner: Runner<R>,
+  ref: IntrinsicReference,
+  args: Array<unknown>,
+  node: AstNode,
 ): Effect.Effect<unknown, unknown, R> => {
  if (typeof ref.receiver === "string") {
    if (ref.name === "replace" || ref.name === "replaceAll") {
@@ -32,7 +41,7 @@ export const invokeIntrinsic = <R>(
  if (typeof ref.receiver === "number") {
    return Effect.succeed(invokeNumberMethod(ref.receiver, ref.name, args, node))
  }
-  if (Array.isArray(ref.receiver)) {
+  if (ref.receiver instanceof ProgramArray) {
    return invokeArrayMethod(runner, ref.receiver, ref.name, args, node)
  }
  if (ref.receiver instanceof Values.Date) {
@@ -215,7 +224,7 @@ const invokeStringMethod = (value: string, name: string, args: Array<unknown>, n
          node,
        )
      }
-      return Array.from(value.matchAll(pattern), matchToValue)
+      return new ProgramArray(Array.from(value.matchAll(pattern), matchToValue))
    }
    case "search": {
      result = value.search(toHostRegex(args[0], name, node))
@@ -288,13 +297,7 @@ const invokeStringReplacer = <R>(
    if (typeof match !== "string" || typeof offset !== "number") {
      throw new InterpreterRuntimeError(`String.${name} produced an invalid replacement match.`, node)
    }
-    if (hasGroups) {
-      const safeGroups: SafeObject = Object.create(null) as SafeObject
-      for (const [key, group] of Object.entries(groups)) {
-        safeGroups[key] = group
-      }
-      callbackArgs[callbackArgs.length - 1] = safeGroups
-    }
+    if (hasGroups) callbackArgs[callbackArgs.length - 1] = record(groups as Record<string, unknown>)
    matches.push({ match, offset, args: callbackArgs })
    return match
  }
@@ -320,14 +323,11 @@ const invokeStringReplacer = <R>(
    let end = 0
    for (const match of matches) {
      const replacement = yield* apply(match.args)
-      // Error values are branded plain objects; toProgram would strip the brand before coercion.
      output.push(
        value.slice(end, match.offset),
        replacement instanceof Values.Promise
          ? "[object Promise]"
-          : errorBrandName(replacement)
-            ? coerceToString(replacement)
-            : coerceToString(toProgram(replacement, `String.${name} replacer result`)),
+          : coerceToString(toProgram(replacement, `String.${name} replacer result`)),
      )
      end = match.offset + match.match.length
    }
@@ -365,7 +365,7 @@ const invokeMapMethod = <R>(
    case "values":
      return Effect.sync(() => Array.from(target.map.values()))
    case "entries":
-      return Effect.sync(() => Array.from(target.map.entries(), ([key, item]): Array<unknown> => [key, item]))
+      return Effect.sync(() => Array.from(target.map.entries(), ([key, item]) => new ProgramArray([key, item])))
    case "forEach": {
      const apply = applyCollectionCallback(runner, args[0], "Map.forEach", node)
      return Effect.gen(function* () {
@@ -404,7 +404,7 @@ const invokeSetMethod = <R>(
    case "values":
      return Effect.sync(() => Array.from(target.set.values()))
    case "entries":
-      return Effect.sync(() => Array.from(target.set.values(), (item): Array<unknown> => [item, item]))
+      return Effect.sync(() => Array.from(target.set.values(), (item) => new ProgramArray([item, item])))
    case "forEach": {
      const apply = applyCollectionCallback(runner, args[0], "Set.forEach", node)
      return Effect.gen(function* () {
@@ -518,28 +518,27 @@ const loadSetRecord = <R>(runner: Runner<R>, source: unknown, name: string, node
      keys: () => Effect.succeed(source.map.keys()),
    })
  }
-  if (source === null || typeof source !== "object" || Values.isValue(source)) {
+  if (!(source instanceof ProgramObject)) {
    throw new InterpreterRuntimeError(`Set.${name} expects a Set-like object.`, node).as("TypeError")
  }
-  const object = source as Record<string, unknown>
  return Effect.gen(function* () {
-    const size = yield* coerceNumericArgument(runner, object.size, node)
+    const size = yield* coerceNumericArgument(runner, get(source, "size"), node)
    if (Number.isNaN(size)) {
      throw new InterpreterRuntimeError(`Set.${name} received a Set-like object with an invalid size.`, node).as(
        "TypeError",
      )
    }
-    if (!isSupportedCallback(object.has) || !isSupportedCallback(object.keys)) {
+    const has = get(source, "has")
+    const keys = get(source, "keys")
+    if (!isSupportedCallback(has) || !isSupportedCallback(keys)) {
      throw new InterpreterRuntimeError(`Set.${name} expects callable 'has' and 'keys' methods.`, node).as("TypeError")
    }
-    const has = object.has
-    const keys = object.keys
    return {
      size: Math.max(Math.trunc(size), 0),
      has: (item: unknown) => Effect.map(runner.invokeCallable(has, [item], node), Boolean),
      keys: () =>
        Effect.flatMap(runner.invokeCallable(keys, [], node), (result) => {
-          if (Array.isArray(result)) return Effect.succeed(result)
+          if (result instanceof ProgramArray) return Effect.succeed(result.items)
          throw new InterpreterRuntimeError(`Set.${name} expected 'keys' to return an iterator.`, node).as("TypeError")
        }),
    }
@@ -604,7 +603,7 @@ const invokeURLSearchParamsMethod = <R>(
    case "values":
      return Effect.sync(() => Array.from(target.params.values()))
    case "entries":
-      return Effect.sync(() => Array.from(target.params.entries(), ([key, value]): Array<unknown> => [key, value]))
+      return Effect.sync(() => Array.from(target.params.entries(), ([key, value]) => new ProgramArray([key, value])))
    case "toString":
      return Effect.sync(() => target.params.toString())
    case "forEach": {
@@ -622,11 +621,12 @@ const invokeURLSearchParamsMethod = <R>(

 const invokeArrayMethod = <R>(
  runner: Runner<R>,
-  target: Array<unknown>,
+  receiver: ProgramArray,
  name: string,
  args: Array<unknown>,
  node: AstNode,
 ): Effect.Effect<unknown, unknown, R> => {
+  const target = receiver.items
  const optNumber = (value: unknown, label: string): number | undefined => {
    if (value === undefined) return undefined
    if (typeof value !== "number")
@@ -638,9 +638,8 @@ const invokeArrayMethod = <R>(
      if (args.length > 1 || (args.length === 1 && typeof args[0] !== "string")) {
        throw new InterpreterRuntimeError("Array.join expects zero arguments or one string separator.", node)
      }
-      const input = toProgram(target, "Array.join input") as Array<unknown>
      return Effect.succeed(
-        input.map((item) => coerceToString(item ?? "")).join(args.length === 0 ? "," : (args[0] as string)),
+        target.map((item) => coerceToString(item ?? "")).join(args.length === 0 ? "," : (args[0] as string)),
      )
    }
    case "includes":
@@ -660,11 +659,15 @@ const invokeArrayMethod = <R>(
    case "slice":
      return Effect.succeed(target.slice(optNumber(args[0], "start"), optNumber(args[1], "end")))
    case "concat":
-      return Effect.succeed(target.concat(...args))
-    case "flat":
-      return Effect.succeed(target.flat(optNumber(args[0], "depth") ?? 1))
+      return Effect.succeed(target.concat(...args.map((item) => (item instanceof ProgramArray ? item.items : item))))
+    case "flat": {
+      const flatten = (items: Array<unknown>, depth: number): Array<unknown> =>
+        items.flatMap((item) => (item instanceof ProgramArray && depth > 0 ? flatten(item.items, depth - 1) : [item]))
+      return Effect.succeed(flatten(target, optNumber(args[0], "depth") ?? 1))
+    }
    case "reverse":
-      return Effect.succeed(target.reverse())
+      target.reverse()
+      return Effect.succeed(receiver)
    case "sort": {
      const length = target.length
      const holeCount = Array.from({ length }, (_, index) => Object.hasOwn(target, index)).filter((own) => !own).length
@@ -676,7 +679,7 @@ const invokeArrayMethod = <R>(
        Array.from({ length: holeCount }, (_, index) => itemCount + index).forEach((index) => {
          Reflect.deleteProperty(target, index)
        })
-        return target
+        return receiver
      })
    }
    case "toSorted":
@@ -695,12 +698,12 @@ const invokeArrayMethod = <R>(
    }
    case "push": {
      // Validate all insertions before mutating to avoid partial cyclic updates.
-      for (const item of args) rejectCircularInsertion(target, item, "Array.push result", node)
+      for (const item of args) rejectCircularInsertion(receiver, item, "Array.push result", node)
      target.push(...args)
      return Effect.succeed(target.length)
    }
    case "unshift": {
-      for (const item of args) rejectCircularInsertion(target, item, "Array.unshift result", node)
+      for (const item of args) rejectCircularInsertion(receiver, item, "Array.unshift result", node)
      target.unshift(...args)
      return Effect.succeed(target.length)
    }
@@ -714,7 +717,7 @@ const invokeArrayMethod = <R>(
      if (args.length === 1) return Effect.succeed(target.splice(start))
      const deleteCount = optNumber(args[1], "delete count") ?? 0
      const inserted = args.slice(2)
-      for (const item of inserted) rejectCircularInsertion(target, item, "Array.splice result", node)
+      for (const item of inserted) rejectCircularInsertion(receiver, item, "Array.splice result", node)
      return Effect.succeed(target.splice(start, deleteCount, ...inserted))
    }
    case "toSpliced": {
@@ -731,23 +734,23 @@ const invokeArrayMethod = <R>(
      return Effect.succeed(copied)
    }
    case "fill": {
-      rejectCircularInsertion(target, args[0], "Array.fill result", node)
-      return Effect.succeed(target.fill(args[0], optNumber(args[1], "start"), optNumber(args[2], "end")))
+      rejectCircularInsertion(receiver, args[0], "Array.fill result", node)
+      target.fill(args[0], optNumber(args[1], "start"), optNumber(args[2], "end"))
+      return Effect.succeed(receiver)
    }
    case "copyWithin":
-      return Effect.succeed(
-        target.copyWithin(
-          optNumber(args[0], "target index") ?? 0,
-          optNumber(args[1], "start") ?? 0,
-          optNumber(args[2], "end"),
-        ),
+      target.copyWithin(
+        optNumber(args[0], "target index") ?? 0,
+        optNumber(args[1], "start") ?? 0,
+        optNumber(args[2], "end"),
      )
+      return Effect.succeed(receiver)
    case "keys":
      return Effect.succeed(Array.from(target.keys()))
    case "values":
      return Effect.succeed([...target])
    case "entries":
-      return Effect.succeed(Array.from(target.entries(), ([index, item]): Array<unknown> => [index, item]))
+      return Effect.succeed(Array.from(target.entries(), ([index, item]) => new ProgramArray([index, item])))
  }

  const apply = applyCollectionCallback(runner, args[0], `Array.${name}`, node)
@@ -760,7 +763,7 @@ const invokeArrayMethod = <R>(
        values.length = length
        for (let index = 0; index < length; index += 1) {
          if (!(index in target)) continue
-          values[index] = yield* apply([target[index], index, target])
+          values[index] = yield* apply([target[index], index, receiver])
        }
        return values
      }
@@ -768,8 +771,8 @@ const invokeArrayMethod = <R>(
        const values: Array<unknown> = []
        for (let index = 0; index < length; index += 1) {
          if (!(index in target)) continue
-          const mapped = yield* apply([target[index], index, target])
-          if (Array.isArray(mapped)) values.push(...mapped)
+          const mapped = yield* apply([target[index], index, receiver])
+          if (mapped instanceof ProgramArray) values.push(...mapped.items)
          else values.push(mapped)
        }
        return values
@@ -779,36 +782,36 @@ const invokeArrayMethod = <R>(
        for (let index = 0; index < length; index += 1) {
          if (!(index in target)) continue
          const item = target[index]
-          if (yield* apply([item, index, target])) values.push(item)
+          if (yield* apply([item, index, receiver])) values.push(item)
        }
        return values
      }
      case "find":
        for (let index = 0; index < length; index += 1) {
          const item = target[index]
-          if (yield* apply([item, index, target])) return item
+          if (yield* apply([item, index, receiver])) return item
        }
        return undefined
      case "findIndex":
        for (let index = 0; index < length; index += 1) {
-          if (yield* apply([target[index], index, target])) return index
+          if (yield* apply([target[index], index, receiver])) return index
        }
        return -1
      case "some":
        for (let index = 0; index < length; index += 1) {
          if (!(index in target)) continue
-          if (yield* apply([target[index], index, target])) return true
+          if (yield* apply([target[index], index, receiver])) return true
        }
        return false
      case "every":
        for (let index = 0; index < length; index += 1) {
          if (!(index in target)) continue
-          if (!(yield* apply([target[index], index, target]))) return false
+          if (!(yield* apply([target[index], index, receiver]))) return false
        }
        return true
      case "forEach":
        for (let index = 0; index < length; index += 1) {
-          if (index in target) yield* apply([target[index], index, target])
+          if (index in target) yield* apply([target[index], index, receiver])
        }
        return undefined
      case "reduce": {
@@ -825,7 +828,7 @@ const invokeArrayMethod = <R>(
        }
        for (let index = start; index < length; index += 1) {
          if (!(index in target)) continue
-          accumulator = yield* apply([accumulator, target[index], index, target])
+          accumulator = yield* apply([accumulator, target[index], index, receiver])
        }
        return accumulator
      }
@@ -843,19 +846,19 @@ const invokeArrayMethod = <R>(
        }
        for (let index = start; index >= 0; index -= 1) {
          if (!(index in target)) continue
-          accumulator = yield* apply([accumulator, target[index], index, target])
+          accumulator = yield* apply([accumulator, target[index], index, receiver])
        }
        return accumulator
      }
      case "findLast":
        for (let index = length - 1; index >= 0; index -= 1) {
          const item = target[index]
-          if (yield* apply([item, index, target])) return item
+          if (yield* apply([item, index, receiver])) return item
        }
        return undefined
      case "findLastIndex":
        for (let index = length - 1; index >= 0; index -= 1) {
-          if (yield* apply([target[index], index, target])) return index
+          if (yield* apply([target[index], index, receiver])) return index
        }
        return -1
    }
@@ -1,7 +1,7 @@
-import type { BlockStatement, Expression, Node, Pattern } from "acorn"
+import type { Node } from "acorn"
 import type { Effect } from "effect"
 import type { DiagnosticKind } from "../codemode.js"
-import type { SafeObject } from "../data.js"
+import type { ProgramObject } from "./objects.js"
 import type { Values } from "../values.js"

 /** Any parsed node; the interpreter narrows on `type` and reads `loc` for diagnostics. */
@@ -20,20 +20,10 @@ export type StatementResult =
  | { kind: "continue"; label?: string }

 export type MemberReference = {
-  target: SafeObject | Array<unknown> | Values.RegExp | Values.URL
+  target: ProgramObject | Values.RegExp | Values.URL
  key: PropertyKey
 }

-export class CodeModeFunction {
-  constructor(
-    readonly parameters: ReadonlyArray<Pattern>,
-    readonly body: BlockStatement | Expression,
-    readonly capturedScopes: ReadonlyArray<Map<string, Binding>>,
-    readonly async: boolean,
-    readonly generator: boolean,
-  ) {}
-}
-
 export type GeneratorRequestKind = "next" | "return" | "throw"

 export class CodeModeGenerator {
@@ -0,0 +1,145 @@
+import type { BlockStatement, Expression, Pattern } from "acorn"
+import { AsyncIteratorSymbol, type Binding, IteratorSymbol } from "./model.js"
+
+/** An object owned by the program: own properties plus a prototype link. */
+export class ProgramObject {
+  readonly props = new Map<PropertyKey, unknown>()
+  constructor(public proto: ProgramObject | null = null) {}
+}
+
+export class ProgramArray extends ProgramObject {
+  constructor(readonly items: Array<unknown> = []) {
+    super()
+  }
+}
+
+export class ProgramError extends ProgramObject {
+  constructor(readonly errorName: string) {
+    super()
+  }
+}
+
+export class ProgramFunction extends ProgramObject {
+  readonly length: number
+  constructor(
+    readonly name: string,
+    readonly parameters: ReadonlyArray<Pattern>,
+    readonly body: BlockStatement | Expression,
+    readonly capturedScopes: ReadonlyArray<Map<string, Binding>>,
+    readonly async: boolean,
+    readonly generator: boolean,
+  ) {
+    super()
+    const optional = parameters.findIndex((p) => p.type === "AssignmentPattern" || p.type === "RestElement")
+    this.length = optional === -1 ? parameters.length : optional
+  }
+}
+
+const MAX_ARRAY_LENGTH = 4_294_967_295
+
+export const parseArrayIndex = (key: string | number): number | undefined => {
+  const property = String(key)
+  if (!/^(0|[1-9]\d*)$/.test(property)) return undefined
+  const index = Number(property)
+  return index < MAX_ARRAY_LENGTH ? index : undefined
+}
+
+const canonical = (key: PropertyKey): string | symbol => (typeof key === "symbol" ? key : String(key))
+
+const index = (target: ProgramObject, key: string | symbol): number | undefined =>
+  target instanceof ProgramArray && typeof key === "string" ? parseArrayIndex(key) : undefined
+
+// Non-enumerable built-in properties: array length, function name and length.
+const builtin = (target: ProgramObject, name: string | symbol): boolean =>
+  (name === "length" && target instanceof ProgramArray) ||
+  ((name === "name" || name === "length") && target instanceof ProgramFunction)
+
+export const hasOwn = (target: ProgramObject, key: PropertyKey): boolean => {
+  const name = canonical(key)
+  const at = index(target, name)
+  if (at !== undefined) return at in (target as ProgramArray).items
+  return builtin(target, name) || target.props.has(name)
+}
+
+export const getOwn = (target: ProgramObject, key: PropertyKey): unknown => {
+  const name = canonical(key)
+  const at = index(target, name)
+  if (at !== undefined) return (target as ProgramArray).items[at]
+  if (target instanceof ProgramArray && name === "length") return target.items.length
+  if (target instanceof ProgramFunction && name === "name") return target.name
+  if (target instanceof ProgramFunction && name === "length") return target.length
+  return target.props.get(name)
+}
+
+export const get = (target: ProgramObject, key: PropertyKey): unknown => {
+  for (let current: ProgramObject | null = target; current !== null; current = current.proto) {
+    if (hasOwn(current, key)) return getOwn(current, key)
+  }
+  return undefined
+}
+
+export const has = (target: ProgramObject, key: PropertyKey): boolean => {
+  for (let current: ProgramObject | null = target; current !== null; current = current.proto) {
+    if (hasOwn(current, key)) return true
+  }
+  return false
+}
+
+export const set = (target: ProgramObject, key: PropertyKey, value: unknown): boolean => {
+  const name = canonical(key)
+  const at = index(target, name)
+  if (at !== undefined) {
+    ;(target as ProgramArray).items[at] = value
+    return true
+  }
+  if (name === "length" && target instanceof ProgramArray) {
+    const length = typeof value === "number" ? value : Number(value)
+    if (!Number.isInteger(length) || length < 0 || length > 4_294_967_295) return false
+    target.items.length = length
+    return true
+  }
+  if (builtin(target, name)) return false
+  target.props.set(name, value)
+  return true
+}
+
+export const remove = (target: ProgramObject, key: PropertyKey): boolean => {
+  const name = canonical(key)
+  const at = index(target, name)
+  if (at !== undefined) return delete (target as ProgramArray).items[at]
+  if (name === "length" && target instanceof ProgramArray) return false
+  if (builtin(target, name)) return true
+  target.props.delete(name)
+  return true
+}
+
+// JS order: array indexes, integer-like keys ascending, other strings, then symbols.
+export const ownKeys = (target: ProgramObject): Array<string | symbol> => {
+  const strings = [...target.props.keys()].filter((key): key is string => typeof key === "string")
+  const symbols = [...target.props.keys()].filter((key): key is symbol => typeof key === "symbol")
+  return [
+    ...(target instanceof ProgramArray ? Object.keys(target.items) : []),
+    ...strings.filter((key) => parseArrayIndex(key) !== undefined).sort((a, b) => Number(a) - Number(b)),
+    ...strings.filter((key) => parseArrayIndex(key) === undefined),
+    ...symbols,
+  ]
+}
+
+export const ownEntries = (target: ProgramObject): Array<[string, unknown]> =>
+  ownKeys(target)
+    .filter((key): key is string => typeof key === "string")
+    .map((key) => [key, getOwn(target, key)])
+
+export const record = (entries: Record<string, unknown>): ProgramObject => {
+  const target = new ProgramObject()
+  for (const [key, value] of Object.entries(entries)) set(target, key, value)
+  return target
+}
+
+export const assign = (target: ProgramObject, source: ProgramObject, skip?: ReadonlySet<PropertyKey>): void => {
+  for (const key of ownKeys(source)) {
+    if (skip?.has(key)) continue
+    if (typeof key === "symbol" && key !== IteratorSymbol && key !== AsyncIteratorSymbol) continue
+    set(target, key, getOwn(source, key))
+  }
+}
@@ -1,13 +1,7 @@
 import { Cause, Deferred, Effect, Exit, Fiber, Scope } from "effect"
 import type { Diagnostic } from "../codemode.js"
-import type { SafeObject } from "../data.js"
-import {
-  type AstNode,
-  CodeModeFunction,
-  InterpreterRuntimeError,
-  ProgramThrow,
-  PromiseInstanceMethodReference,
-} from "./model.js"
+import { type AstNode, InterpreterRuntimeError, ProgramThrow, PromiseInstanceMethodReference } from "./model.js"
+import { get, ProgramArray, ProgramFunction, ProgramObject, record } from "./objects.js"
 import { HostFunction, requiresNew, sync } from "./host.js"
 import { caughtErrorValue, normalizeError } from "./errors.js"
 import { typeofValue } from "./references.js"
@@ -111,8 +105,8 @@ export const resolvePromiseValue = <R>(
 ): Effect.Effect<unknown, unknown, R> => {
  if (own?.promise !== undefined && value === own.promise) return Effect.fail(selfResolutionError(node))
  if (value instanceof Values.Promise) return runner.settlePromise(value)
-  if (value === null || typeof value !== "object" || !Object.hasOwn(value, "then")) return Effect.succeed(value)
-  const then = (value as SafeObject).then
+  if (!(value instanceof ProgramObject)) return Effect.succeed(value)
+  const then = get(value, "then")
  if (typeofValue(then) !== "function") return Effect.succeed(value)

  return Effect.gen(function* () {
@@ -174,10 +168,12 @@ const invokePromiseMethod = <R>(
      }

      if (name === "all") {
-        return yield* settleAfterTurn(
-          Effect.all(
-            items.map((item) => Effect.flatten(promises.await(item))),
-            { concurrency: "unbounded" },
+        return new ProgramArray(
+          yield* settleAfterTurn(
+            Effect.all(
+              items.map((item) => Effect.flatten(promises.await(item))),
+              { concurrency: "unbounded" },
+            ),
          ),
        )
      }
@@ -186,19 +182,14 @@ const invokePromiseMethod = <R>(
        for (const item of items) {
          const exit = yield* promises.await(item)
          if (Exit.isSuccess(exit)) {
-            outcomes.push(Object.assign(Object.create(null) as SafeObject, { status: "fulfilled", value: exit.value }))
+            outcomes.push(record({ status: "fulfilled", value: exit.value }))
            continue
          }
          if (Cause.hasInterruptsOnly(exit.cause)) return yield* Effect.failCause(exit.cause)
-          outcomes.push(
-            Object.assign(Object.create(null) as SafeObject, {
-              status: "rejected",
-              reason: caughtErrorValue(Cause.squash(exit.cause)),
-            }),
-          )
+          outcomes.push(record({ status: "rejected", reason: caughtErrorValue(Cause.squash(exit.cause)) }))
        }
        yield* Effect.yieldNow
-        return outcomes
+        return new ProgramArray(outcomes)
      }
      if (name === "race") {
        if (items.length === 0) {
@@ -253,7 +244,7 @@ const constructPromise = <R>(
  executor: unknown,
  node: AstNode,
 ): Effect.Effect<Values.Promise, unknown, R> => {
-  if (!(executor instanceof CodeModeFunction)) {
+  if (!(executor instanceof ProgramFunction)) {
    throw new InterpreterRuntimeError(
      "new Promise(...) expects an executor function (e.g. new Promise((resolve, reject) => { ... })).",
      node,
@@ -3,20 +3,18 @@ import { Values } from "../values.js"
 import { HostFunction, HostNamespace } from "./host.js"
 import {
  type AstNode,
-  AsyncIteratorSymbol,
-  CodeModeFunction,
  CodeModeGenerator,
  GeneratorMethodReference,
  InterpreterRuntimeError,
  IntrinsicReference,
-  IteratorSymbol,
  PromiseInstanceMethodReference,
 } from "./model.js"
+import { getOwn, ownKeys, ProgramArray, ProgramFunction, ProgramObject } from "./objects.js"

 export const isRuntimeReference = (value: unknown): boolean =>
  value instanceof HostFunction ||
  value instanceof HostNamespace ||
-  value instanceof CodeModeFunction ||
+  value instanceof ProgramFunction ||
  value instanceof CodeModeGenerator ||
  value instanceof GeneratorMethodReference ||
  value instanceof ToolReference ||
@@ -26,11 +24,8 @@ export const isRuntimeReference = (value: unknown): boolean =>
  Values.isValue(value)

 function* childValues(value: object): Generator {
-  for (const key of Reflect.ownKeys(value)) {
-    if (!Object.prototype.propertyIsEnumerable.call(value, key)) continue
-    if (typeof key === "symbol" && key !== AsyncIteratorSymbol && key !== IteratorSymbol) continue
-    yield Reflect.get(value, key)
-  }
+  if (!(value instanceof ProgramObject)) return
+  for (const key of ownKeys(value)) yield getOwn(value, key)
 }

 // Depth-first search over a value tree. `match` stops the walk; `skip` prunes a subtree without matching it.
@@ -79,7 +74,7 @@ export const rejectCircularInsertion = (

 export const describeValue = (value: unknown): string => {
  if (value === null) return "null"
-  if (Array.isArray(value)) return "an array"
+  if (value instanceof ProgramArray) return "an array"
  if (value instanceof Values.Promise) return "an un-awaited Promise"
  if (value instanceof ToolReference) return "a tool reference"
  if (value instanceof Values.Date) return "a Date"
@@ -97,7 +92,7 @@ export const describeValue = (value: unknown): string => {
 export const typeofValue = (value: unknown): string => {
  if (
    value instanceof HostFunction ||
-    value instanceof CodeModeFunction ||
+    value instanceof ProgramFunction ||
    value instanceof GeneratorMethodReference ||
    value instanceof IntrinsicReference ||
    value instanceof PromiseInstanceMethodReference
@@ -108,12 +103,3 @@ export const typeofValue = (value: unknown): string => {
  if (value instanceof ToolReference) return value.path.length > 0 ? "function" : "object"
  return typeof value
 }
-
-const MAX_ARRAY_LENGTH = 4_294_967_295
-
-export const parseArrayIndex = (key: string | number): number | undefined => {
-  const property = String(key)
-  if (!/^(0|[1-9]\d*)$/.test(property)) return undefined
-  const index = Number(property)
-  return index < MAX_ARRAY_LENGTH ? index : undefined
-}
@@ -2,7 +2,8 @@ import { Effect, Exit } from "effect"
 import { Values } from "../values.js"
 import { coerceToString } from "../stdlib/value.js"
 import { HostFunction } from "./host.js"
-import { type AstNode, CodeModeFunction, InterpreterRuntimeError, IntrinsicReference } from "./model.js"
+import { type AstNode, InterpreterRuntimeError, IntrinsicReference } from "./model.js"
+import { get, has, ProgramFunction, ProgramObject } from "./objects.js"
 import { typeofValue } from "./references.js"

 export type IteratorCursor<R> = {
@@ -12,7 +13,7 @@ export type IteratorCursor<R> = {

 /** Everything a host function needs to call back into the program. */
 export type Runner<R> = {
-  readonly invokeFunction: (fn: CodeModeFunction, args: Array<unknown>) => Effect.Effect<unknown, unknown, R>
+  readonly invokeFunction: (fn: ProgramFunction, args: Array<unknown>) => Effect.Effect<unknown, unknown, R>
  readonly invokeCallable: (
    callable: unknown,
    args: Array<unknown>,
@@ -42,13 +43,14 @@ export const toPrimitive = <R>(
  if (Values.isValue(value)) {
    return Effect.succeed(value instanceof Values.Date && hint === "number" ? value.time : coerceToString(value))
  }
-  const object = value as Record<string, unknown>
+  if (!(value instanceof ProgramObject)) return Effect.succeed(value)
  const order = hint === "number" ? ["valueOf", "toString"] : ["toString", "valueOf"]
  return Effect.gen(function* () {
    for (const method of order) {
-      if (method === "toString" && !Object.hasOwn(object, "toString")) return coerceToString(value)
-      if (!Object.hasOwn(object, method) || typeofValue(object[method]) !== "function") continue
-      const result = yield* runner.invokeCallable(object[method], [], node)
+      if (method === "toString" && !has(value, "toString")) return coerceToString(value)
+      const callable = get(value, method)
+      if (typeofValue(callable) !== "function") continue
+      const result = yield* runner.invokeCallable(callable, [], node)
      if (result === null || (typeof result !== "object" && typeof result !== "function")) return result
    }
    throw new InterpreterRuntimeError("Cannot convert object to primitive value.", node).as("TypeError")
@@ -59,10 +61,10 @@ export const toPrimitive = <R>(
 // Array.from mappers, and promise reactions all admit exactly these callables.
 // Admission means dispatchable, not necessarily invocable: new-requiring
 // constructors pass the gate and throw a TypeError on call, like JS.
-export type SupportedCallback = CodeModeFunction | HostFunction<unknown> | IntrinsicReference
+export type SupportedCallback = ProgramFunction | HostFunction<unknown> | IntrinsicReference

 export const isSupportedCallback = (value: unknown): value is SupportedCallback =>
-  value instanceof CodeModeFunction ||
+  value instanceof ProgramFunction ||
  (value instanceof HostFunction && value.callback) ||
  value instanceof IntrinsicReference

@@ -1,6 +1,7 @@
 import type {
  ArrayExpression,
  ArrayPattern,
+  AssignmentPattern,
  ArrowFunctionExpression,
  AssignmentExpression,
  AssignmentProperty,
@@ -41,13 +42,12 @@ import type {
  YieldExpression,
 } from "acorn"
 import { Cause, Deferred, Effect, Exit } from "effect"
-import { ToolRuntimeError, type SafeObject, toProgram } from "../data.js"
+import { ToolRuntimeError, toProgram } from "../data.js"
 import { ToolReference } from "../tool-runtime.js"
 import {
  type AstNode,
  AsyncIteratorSymbol,
  type Binding,
-  CodeModeFunction,
  CodeModeGenerator,
  ComputedValue,
  GeneratorMethodReference,
@@ -55,9 +55,7 @@ import {
  type GeneratorRequestKind,
  IntrinsicReference,
  InterpreterRuntimeError,
-  isRecord,
  IteratorSymbol,
-  IteratorSymbols,
  type MemberReference,
  OptionalShortCircuit,
  PromiseInstanceMethodReference,
@@ -66,16 +64,28 @@ import {
  unsupportedSyntax,
 } from "./model.js"
 import { caughtErrorValue } from "./errors.js"
-import { globals } from "./globals.js"
+import { globals, type Host } from "./globals.js"
 import { HostFunction, HostNamespace } from "./host.js"
 import { invokeIntrinsic } from "./methods.js"
+import {
+  assign,
+  get,
+  has,
+  ownKeys,
+  parseArrayIndex,
+  ProgramArray,
+  ProgramFunction,
+  ProgramObject,
+  record,
+  remove,
+  set,
+} from "./objects.js"
 import { preserveConsumerError, type Runner } from "./runner.js"
 import { invokePromiseInstanceMethod, PromiseRuntime, resolvePromise, resolvePromiseValue } from "./promises.js"
 import {
  containsOpaqueReference,
  describeValue,
  isRuntimeReference,
-  parseArrayIndex,
  rejectCircularInsertion,
  typeofValue,
 } from "./references.js"
@@ -118,14 +128,11 @@ const calleeDescription = (callee: Expression | Super | undefined): string => {
  return "The called value"
 }

-const hasOwn = (value: unknown, key: PropertyKey): boolean =>
-  value !== null && typeof value === "object" && Object.hasOwn(value, key)
-
 const constructorName = (value: unknown): string | undefined => {
  if (typeof value === "string") return "String"
  if (typeof value === "number") return "Number"
  if (typeof value === "boolean") return "Boolean"
-  if (Array.isArray(value)) return "Array"
+  if (value instanceof ProgramArray) return "Array"
  if (value instanceof Values.Date) return "Date"
  if (value instanceof Values.RegExp) return "RegExp"
  if (value instanceof Values.Map) return "Map"
@@ -133,7 +140,7 @@ const constructorName = (value: unknown): string | undefined => {
  if (value instanceof Values.URL) return "URL"
  if (value instanceof Values.URLSearchParams) return "URLSearchParams"
  if (value instanceof Values.Promise) return "Promise"
-  if (value === null || typeof value !== "object" || isRuntimeReference(value)) return undefined
+  if (!(value instanceof ProgramObject) || value instanceof ProgramFunction) return undefined
  return errorBrandName(value) ?? "Object"
 }

@@ -230,7 +237,7 @@ const loopDeclaration = (left: VariableDeclaration | Pattern, statement: "for...
 }

 type CustomIterator = {
-  iterator: SafeObject | CodeModeGenerator
+  iterator: ProgramObject | CodeModeGenerator
  next: unknown
  asynchronous: boolean
 }
@@ -247,13 +254,6 @@ const isOpaqueMemberReference = (value: unknown): value is OpaqueMemberReference
  value instanceof IntrinsicReference ||
  value instanceof GeneratorMethodReference

-const copyIteratorSymbols = (source: object, target: object, consumed?: ReadonlySet<PropertyKey>): void => {
-  for (const symbol of IteratorSymbols) {
-    if (!consumed?.has(symbol) && Object.hasOwn(source, symbol))
-      Reflect.set(target, symbol, Reflect.get(source, symbol))
-  }
-}
-
 type GeneratorRequest = {
  kind: GeneratorRequestKind
  value: unknown
@@ -285,6 +285,7 @@ export class Runtime<R> {
    readonly toolKeys: (path: ReadonlyArray<string>) => ReadonlyArray<string>,
    readonly promises: PromiseRuntime<R>,
    readonly logs: Array<string> = [],
+    extraGlobals: (host: Host<R>) => ReadonlyArray<readonly [string, unknown]> = () => [],
  ) {
    const globalScope = new Map<string, Binding>()
    // Calling back into the program never reads frame state, so any frame serves; the root is always alive.
@@ -295,7 +296,7 @@ export class Runtime<R> {
      settlePromise: (promise) => this.root.settlePromise(promise),
      syncIterator: (value, node) => this.root.syncIterator(value, node),
    }
-    this.builtins = new Map(globals(this))
+    this.builtins = new Map([...globals(this), ...extraGlobals(this)])
    for (const [name, value] of this.builtins) globalScope.set(name, { mutable: false, value })
  }

@@ -434,8 +435,19 @@ class Frame<R> {
    }).pipe(Effect.ensuring(Effect.sync(() => self.scopes.pop())))
  }

-  private createFunction(node: FunctionDeclaration | FunctionExpression | ArrowFunctionExpression): CodeModeFunction {
-    return new CodeModeFunction(node.params, node.body, this.scopes.capture(), node.async, node.generator)
+  private createFunction(
+    node: FunctionDeclaration | FunctionExpression | ArrowFunctionExpression,
+    name = node.type === "ArrowFunctionExpression" ? "" : (node.id?.name ?? ""),
+  ): ProgramFunction {
+    return new ProgramFunction(name, node.params, node.body, this.scopes.capture(), node.async, node.generator)
+  }
+
+  // NamedEvaluation: an anonymous function definition takes the name of what it is assigned to.
+  private evaluateNamed(node: Expression, name: string): Effect.Effect<unknown, unknown, R> {
+    if (node.type === "ArrowFunctionExpression" || (node.type === "FunctionExpression" && !node.id)) {
+      return Effect.sync(() => this.createFunction(node, name))
+    }
+    return this.evaluateExpression(node)
  }

  private hoistFunctions(statements: ReadonlyArray<Statement | ModuleDeclaration>): void {
@@ -722,22 +734,26 @@ class Frame<R> {
  }

  syncIterator(value: unknown, node: AstNode) {
-    const iterator = Array.isArray(value)
-      ? value[Symbol.iterator]()
-      : typeof value === "string"
-        ? value[Symbol.iterator]()
-        : value instanceof Values.Map
-          ? value.map.entries()
-          : value instanceof Values.Set
-            ? value.set.values()
-            : value instanceof Values.URLSearchParams
-              ? value.params.entries()
-              : undefined
+    const iterator =
+      value instanceof ProgramArray
+        ? value.items[Symbol.iterator]()
+        : typeof value === "string"
+          ? value[Symbol.iterator]()
+          : value instanceof Values.Map
+            ? value.map.entries()
+            : value instanceof Values.Set
+              ? value.set.values()
+              : value instanceof Values.URLSearchParams
+                ? value.params.entries()
+                : undefined
    if (iterator !== undefined) {
      return Effect.succeed({
        next: Effect.sync(() => {
          const step = iterator.next()
-          return { done: Boolean(step.done), value: step.value }
+          return {
+            done: Boolean(step.done),
+            value: Array.isArray(step.value) ? new ProgramArray(step.value) : step.value,
+          }
        }),
        close: Effect.void,
      })
@@ -762,9 +778,9 @@ class Frame<R> {
        asynchronous: value.asynchronous,
      })
    }
-    if (!isRecord(value) || isRuntimeReference(value)) return Effect.undefined
-    const asyncMethod = allowAsync ? Reflect.get(value, AsyncIteratorSymbol) : undefined
-    const method = asyncMethod ?? Reflect.get(value, IteratorSymbol)
+    if (!(value instanceof ProgramObject)) return Effect.undefined
+    const asyncMethod = allowAsync ? get(value, AsyncIteratorSymbol) : undefined
+    const method = asyncMethod ?? get(value, IteratorSymbol)
    if (method === undefined || method === null) return Effect.undefined
    const self = this
    return Effect.map(
@@ -776,7 +792,7 @@ class Frame<R> {
          next:
            object instanceof CodeModeGenerator
              ? new GeneratorMethodReference(object, "next")
-              : self.requireIteratorMethod(object.next, "Iterator next", node),
+              : self.requireIteratorMethod(get(object, "next"), "Iterator next", node),
          asynchronous: asyncMethod !== undefined && asyncMethod !== null,
        }
      },
@@ -792,7 +808,7 @@ class Frame<R> {
          "Iterator next() result",
          node,
        )
-        return { done: Boolean(object.done), value: object.value }
+        return { done: Boolean(get(object, "done")), value: get(object, "value") }
      }

      const called = yield* Effect.exit(self.invokeCallable(iterator.next, [], node))
@@ -803,7 +819,7 @@ class Frame<R> {
      const captured = yield* Effect.exit(
        Effect.sync(() => {
          const object = self.requireIteratorObject(called.value, "Iterator next() result", node)
-          return { done: Boolean(object.done), value: object.value }
+          return { done: Boolean(get(object, "done")), value: get(object, "value") }
        }),
      )
      if (!Exit.isSuccess(captured)) {
@@ -823,7 +839,7 @@ class Frame<R> {
    const close =
      iterator.iterator instanceof CodeModeGenerator
        ? new GeneratorMethodReference(iterator.iterator, "return")
-        : iterator.iterator.return
+        : get(iterator.iterator, "return")
    if (close === undefined || close === null) return iterator.asynchronous || !awaiting ? Effect.void : Effect.yieldNow
    const self = this
    return Effect.gen(function* () {
@@ -843,7 +859,7 @@ class Frame<R> {
        return yield* Effect.failCause(called.cause)
      }
      const captured = yield* Effect.exit(
-        Effect.sync(() => self.requireIteratorObject(called.value, "Iterator return() result", node).value),
+        Effect.sync(() => get(self.requireIteratorObject(called.value, "Iterator return() result", node), "value")),
      )
      if (!Exit.isSuccess(captured)) {
        if (awaiting) yield* Effect.yieldNow
@@ -853,12 +869,12 @@ class Frame<R> {
    })
  }

-  private requireIteratorObject(value: unknown, context: string, node: AstNode): SafeObject {
-    if (isRecord(value) && !isRuntimeReference(value)) return value
+  private requireIteratorObject(value: unknown, context: string, node: AstNode): ProgramObject {
+    if (value instanceof ProgramObject) return value
    throw new InterpreterRuntimeError(`${context} must be an object.`, node).as("TypeError")
  }

-  private requireIterator(value: unknown, node: AstNode): SafeObject | CodeModeGenerator {
+  private requireIterator(value: unknown, node: AstNode): ProgramObject | CodeModeGenerator {
    return value instanceof CodeModeGenerator
      ? value
      : this.requireIteratorObject(value, "Iterator method result", node)
@@ -873,7 +889,7 @@ class Frame<R> {
  private enumerableKeys(value: unknown, node: AstNode): Array<string> {
    if (value instanceof ToolReference) return [...this.runtime.toolKeys(value.path)]
    if (value === null || value === undefined) return []
-    return Object.keys(enumerableSource("for...in", value, node))
+    return ownKeys(enumerableSource("for...in", value, node)).filter((key): key is string => typeof key === "string")
  }

  private evaluateForInStatement(
@@ -1019,11 +1035,14 @@ class Frame<R> {

        const init = declaration.init
        // `var x` alone is a no-op: the binding was hoisted on function entry.
+        const id = declaration.id
+        const evaluate = (init: Expression) =>
+          id.type === "Identifier" ? self.evaluateNamed(init, id.name) : self.evaluateExpression(init)
        if (kind === "var") {
-          if (init) yield* self.assignPattern(declaration.id, yield* self.evaluateExpression(init), declaration)
+          if (init) yield* self.assignPattern(id, yield* evaluate(init), declaration)
          continue
        }
-        const value = init ? yield* self.evaluateExpression(init) : undefined
+        const value = init ? yield* evaluate(init) : undefined
        yield* self.declarePattern(declaration.id, value, kind !== "const", declaration, true)
      }
    })
@@ -1046,13 +1065,13 @@ class Frame<R> {
      }

      if (pattern.type === "AssignmentPattern") {
-        const resolved = value === undefined ? yield* self.evaluateExpression(pattern.right) : value
+        const resolved = value === undefined ? yield* self.evaluateDefault(pattern) : value
        yield* self.declarePattern(pattern.left, resolved, mutable, node, initialize)
        return
      }

      if (pattern.type === "ObjectPattern") {
-        if (value === null || typeof value !== "object" || isRuntimeReference(value)) {
+        if (!(value instanceof ProgramObject)) {
          throw new InterpreterRuntimeError(
            `Object destructuring requires a data object or array value, received ${describeValue(value)}.`,
            pattern,
@@ -1063,11 +1082,8 @@ class Frame<R> {
        const consumed = new Set<PropertyKey>()
        for (const property of pattern.properties) {
          if (property.type === "RestElement") {
-            const rest: SafeObject = Object.create(null) as SafeObject
-            for (const [key, item] of Object.entries(value as SafeObject)) {
-              if (!consumed.has(key)) rest[key] = item
-            }
-            copyIteratorSymbols(value, rest, consumed)
+            const rest = new ProgramObject()
+            assign(rest, value, consumed)
            yield* self.declarePattern(property.argument, rest, mutable, property, initialize)
            continue
          }
@@ -1076,7 +1092,7 @@ class Frame<R> {
          consumed.add(typeof key === "symbol" ? key : String(key))
          yield* self.declarePattern(
            property.value,
-            self.destructuringPropertyValue(value as SafeObject | Array<unknown>, key),
+            self.destructuringPropertyValue(value, key),
            mutable,
            property,
            initialize,
@@ -1109,13 +1125,13 @@ class Frame<R> {
      }

      if (pattern.type === "AssignmentPattern") {
-        const resolved = value === undefined ? yield* self.evaluateExpression(pattern.right) : value
+        const resolved = value === undefined ? yield* self.evaluateDefault(pattern) : value
        yield* self.assignPattern(pattern.left, resolved, node)
        return
      }

      if (pattern.type === "ObjectPattern") {
-        if (value === null || typeof value !== "object" || isRuntimeReference(value)) {
+        if (!(value instanceof ProgramObject)) {
          throw new InterpreterRuntimeError(
            `Object destructuring requires a data object or array value, received ${describeValue(value)}.`,
            pattern,
@@ -1123,21 +1139,17 @@ class Frame<R> {
          )
        }

-        const source = value as SafeObject | Array<unknown>
        const consumed = new Set<PropertyKey>()
        for (const property of pattern.properties) {
          if (property.type === "RestElement") {
-            const rest: SafeObject = Object.create(null) as SafeObject
-            for (const [key, item] of Object.entries(source)) {
-              if (!consumed.has(key)) rest[key] = item
-            }
-            copyIteratorSymbols(source, rest, consumed)
+            const rest = new ProgramObject()
+            assign(rest, value, consumed)
            yield* self.assignPattern(property.argument, rest, property)
            continue
          }
          const key = yield* self.destructuringPropertyKey(property)
          consumed.add(typeof key === "symbol" ? key : String(key))
-          yield* self.assignPattern(property.value, self.destructuringPropertyValue(source, key), property)
+          yield* self.assignPattern(property.value, self.destructuringPropertyValue(value, key), property)
        }
        return
      }
@@ -1152,6 +1164,12 @@ class Frame<R> {
    })
  }

+  private evaluateDefault(pattern: AssignmentPattern): Effect.Effect<unknown, unknown, R> {
+    return pattern.left.type === "Identifier"
+      ? this.evaluateNamed(pattern.right, pattern.left.name)
+      : this.evaluateExpression(pattern.right)
+  }
+
  private destructureArrayPattern(
    pattern: ArrayPattern,
    value: unknown,
@@ -1171,7 +1189,7 @@ class Frame<R> {
          if (element === null) continue
          yield* consume(
            element.type === "RestElement" ? element.argument : element,
-            element.type === "RestElement" ? [] : undefined,
+            element.type === "RestElement" ? new ProgramArray() : undefined,
            element,
          )
          if (element.type === "RestElement") return
@@ -1188,7 +1206,7 @@ class Frame<R> {
            done = next.done
            if (!done) rest.push(next.value)
          }
-          yield* consume(element.argument, rest, element)
+          yield* consume(element.argument, new ProgramArray(rest), element)
          return
        }
        const consumed = consume(element, step.done ? undefined : step.value, pattern)
@@ -1211,11 +1229,9 @@ class Frame<R> {
    throw unsupportedSyntax(keyNode.type, keyNode)
  }

-  private destructuringPropertyValue(source: SafeObject | Array<unknown>, key: PropertyKey): unknown {
-    if (!Array.isArray(source)) return Reflect.get(source, key)
-    if (key === "length") return source.length
-    if (typeof key === "number") return source[key]
-    if (Object.hasOwn(source, key)) return Reflect.get(source, key)
+  private destructuringPropertyValue(source: ProgramObject, key: PropertyKey): unknown {
+    if (!(source instanceof ProgramArray)) return get(source, key)
+    if (has(source, key)) return get(source, key)
    if (typeof key === "string" && arrayMethods.has(key)) return new IntrinsicReference(source, key)
    return undefined
  }
@@ -1293,7 +1309,7 @@ class Frame<R> {
        // otherwise; say `new` is unsupported for them and point at the plain call.
        const name = calleeDescription(node.callee)
        const message =
-          callee instanceof CodeModeFunction
+          callee instanceof ProgramFunction
            ? `${name} cannot be constructed: user-defined constructors and classes are not supported. Call it as a function that returns a plain object instead.`
            : callee instanceof HostFunction
              ? `new ${name}(...) is not supported; call ${name}(...) without new instead.`
@@ -1321,6 +1337,9 @@ class Frame<R> {
  private applyBinaryOperator(operator: string, lhs: unknown, rhs: unknown, node: AstNode): unknown {
    if (operator === "===") return lhs === rhs
    if (operator === "!==") return lhs !== rhs
+    if (operator === "in" && rhs instanceof ProgramObject && !containsOpaqueReference(lhs)) {
+      return has(rhs, lhs !== null && typeof lhs === "object" ? coerceToString(lhs) : (lhs as PropertyKey))
+    }
    if (containsOpaqueReference(lhs) || containsOpaqueReference(rhs)) {
      throw new InterpreterRuntimeError("Binary operators require data values.", node, "InvalidDataValue")
    }
@@ -1373,11 +1392,10 @@ class Frame<R> {
      case ">>>":
        return (l as number) >>> (r as number)
      case "in":
-        if (rhs === null || typeof rhs !== "object") {
+        if (!(rhs instanceof ProgramObject)) {
          throw new InterpreterRuntimeError("The 'in' operator requires a data object on the right-hand side.", node)
        }
-        // Never expose properties inherited from host prototypes.
-        return Object.hasOwn(rhs as object, coerceOperand(lhs) as PropertyKey)
+        return has(rhs, coerceOperand(lhs) as PropertyKey)
      default:
        throw new InterpreterRuntimeError(`Unsupported binary operator '${operator}'.`, node)
    }
@@ -1454,7 +1472,7 @@ class Frame<R> {
          const next = toProgram(self.applyCompoundAssignment(operator, current, rightValue, node), "Assignment result")
          return self.scopes.set(name, next, left)
        }
-        const rightValue = yield* self.evaluateExpression(node.right)
+        const rightValue = yield* self.evaluateNamed(node.right, name)
        return self.scopes.set(name, rightValue, left)
      }
      if (left.type === "MemberExpression") {
@@ -1486,7 +1504,7 @@ class Frame<R> {
      return Effect.gen(function* () {
        const current = self.scopes.get(name, left)
        if (!shouldAssign(current)) return current
-        const rightValue = yield* self.evaluateExpression(node.right)
+        const rightValue = yield* self.evaluateNamed(node.right, name)
        return self.scopes.set(name, rightValue, left)
      })
    }
@@ -1575,7 +1593,7 @@ class Frame<R> {
        }
        return yield* self.createToolCallPromise(callable.path, args)
      }
-      if (callable instanceof CodeModeFunction) {
+      if (callable instanceof ProgramFunction) {
        return yield* self.invokeFunction(callable, args)
      }
      if (callable instanceof GeneratorMethodReference) {
@@ -1626,7 +1644,7 @@ class Frame<R> {
    })
  }

-  invokeFunction(fn: CodeModeFunction, args: Array<unknown>): Effect.Effect<unknown, unknown, R> {
+  invokeFunction(fn: ProgramFunction, args: Array<unknown>): Effect.Effect<unknown, unknown, R> {
    const invocation = new Frame(this.runtime, new ScopeStack([...fn.capturedScopes, new Map()]))
    const run = Effect.gen(function* () {
      // Seed all parameters first so defaults cannot fall through to same-named outer bindings.
@@ -1638,7 +1656,13 @@ class Frame<R> {
      }
      for (const [index, parameter] of fn.parameters.entries()) {
        if (parameter.type === "RestElement") {
-          yield* invocation.declarePattern(parameter.argument, args.slice(index), true, parameter, true)
+          yield* invocation.declarePattern(
+            parameter.argument,
+            new ProgramArray(args.slice(index)),
+            true,
+            parameter,
+            true,
+          )
          break
        }
        yield* invocation.declarePattern(parameter, args[index], true, parameter, true)
@@ -1690,12 +1714,12 @@ class Frame<R> {
      }
      if (state.completed) {
        if (kind === "throw") return Effect.fail(new ProgramThrow(value))
-        return Effect.succeed({ value: kind === "return" ? value : undefined, done: true })
+        return Effect.succeed(record({ value: kind === "return" ? value : undefined, done: true }))
      }
      if (!state.started && kind !== "next") {
        state.completed = true
        if (kind === "throw") return Effect.fail(new ProgramThrow(value))
-        return Effect.succeed({ value, done: true })
+        return Effect.succeed(record({ value, done: true }))
      }

      state.pending.push(request)
@@ -1725,7 +1749,7 @@ class Frame<R> {
          if (active) {
            Deferred.doneUnsafe(
              active.response,
-              Exit.isSuccess(exit) ? Exit.succeed({ value: exit.value, done: true }) : exit,
+              Exit.isSuccess(exit) ? Exit.succeed(record({ value: exit.value, done: true })) : exit,
            )
          }
          yield* invocation.completeGeneratorRequests(state, asynchronous)
@@ -1752,13 +1776,13 @@ class Frame<R> {
          const resolved = yield* Effect.exit(self.awaitValue(pending.value))
          Deferred.doneUnsafe(
            pending.response,
-            Exit.isSuccess(resolved) ? Exit.succeed({ value: resolved.value, done: true }) : resolved,
+            Exit.isSuccess(resolved) ? Exit.succeed(record({ value: resolved.value, done: true })) : resolved,
          )
          continue
        }
        Deferred.doneUnsafe(
          pending.response,
-          Exit.succeed({ value: pending.kind === "return" ? pending.value : undefined, done: true }),
+          Exit.succeed(record({ value: pending.kind === "return" ? pending.value : undefined, done: true })),
        )
      }
    })
@@ -1803,7 +1827,7 @@ class Frame<R> {
  private suspendGenerator(value: unknown, node: AstNode): Effect.Effect<unknown, unknown, R> {
    const state = this.generatorState
    if (!state?.active) throw new InterpreterRuntimeError("Generator has no active request.", node)
-    Deferred.doneUnsafe(state.active.response, Exit.succeed({ value, done: false }))
+    Deferred.doneUnsafe(state.active.response, Exit.succeed(record({ value, done: false })))
    state.active = undefined
    return Effect.flatMap(this.takeGeneratorRequest(state), (request) => {
      state.active = request
@@ -1819,7 +1843,7 @@ class Frame<R> {
    const self = this
    return Effect.gen(function* () {
      if (
-        Array.isArray(value) ||
+        value instanceof ProgramArray ||
        typeof value === "string" ||
        value instanceof Values.Map ||
        value instanceof Values.Set ||
@@ -1860,7 +1884,7 @@ class Frame<R> {
            ? iterator.next
            : iterator.iterator instanceof CodeModeGenerator
              ? new GeneratorMethodReference(iterator.iterator, kind)
-              : iterator.iterator[kind]
+              : get(iterator.iterator, kind)
        if (method === undefined || method === null) {
          if (kind === "return") return yield* Effect.fail(new GeneratorReturn(input))
          yield* self.closeIterator(iterator, node, self.generatorAsync)
@@ -1878,11 +1902,11 @@ class Frame<R> {
          `Iterator ${kind}() result`,
          node,
        )
-        const done = Boolean(result.done)
+        const done = Boolean(get(result, "done"))
        const resultValue: unknown =
          self.generatorAsync && !iterator.asynchronous
-            ? yield* self.awaitAsyncFromSyncValue(iterator, result.value, node, kind !== "return" && !done)
-            : result.value
+            ? yield* self.awaitAsyncFromSyncValue(iterator, get(result, "value"), node, kind !== "return" && !done)
+            : get(result, "value")
        if (done) {
          if (kind === "return") return yield* Effect.fail(new GeneratorReturn(resultValue))
          return resultValue
@@ -1904,17 +1928,15 @@ class Frame<R> {
    })
  }

-  private evaluateObjectExpression(node: ObjectExpression): Effect.Effect<Record<string, unknown>, unknown, R> {
-    const objectValue: Record<string, unknown> = Object.create(null) as Record<string, unknown>
+  private evaluateObjectExpression(node: ObjectExpression): Effect.Effect<ProgramObject, unknown, R> {
+    const objectValue = new ProgramObject()
    const self = this
    return Effect.gen(function* () {
      for (const property of node.properties) {
        if (property.type === "SpreadElement") {
          const spread = yield* self.evaluateExpression(property.argument)
          if (spread === null || spread === undefined) continue
-          const from = enumerableSource("Object spread", spread, property)
-          for (const [key, value] of Object.entries(from)) objectValue[key] = value
-          if (typeof from === "object") copyIteratorSymbols(from, objectValue)
+          assign(objectValue, enumerableSource("Object spread", spread, property))
          continue
        }

@@ -1936,14 +1958,20 @@ class Frame<R> {
          throw new InterpreterRuntimeError("Unsupported object property key shape.", keyNode)
        }

-        Reflect.set(objectValue, key, yield* self.evaluateExpression(property.value))
+        const name =
+          key === IteratorSymbol
+            ? "[Symbol.iterator]"
+            : key === AsyncIteratorSymbol
+              ? "[Symbol.asyncIterator]"
+              : String(key)
+        set(objectValue, key, yield* self.evaluateNamed(property.value, name))
      }

      return objectValue
    })
  }

-  private evaluateArrayExpression(node: ArrayExpression): Effect.Effect<Array<unknown>, unknown, R> {
+  private evaluateArrayExpression(node: ArrayExpression): Effect.Effect<ProgramArray, unknown, R> {
    const values: Array<unknown> = []

    const self = this
@@ -1968,7 +1996,7 @@ class Frame<R> {
          values.push(yield* self.evaluateExpression(element))
        }
      }
-      return values
+      return new ProgramArray(values)
    })
  }

@@ -2055,7 +2083,11 @@ class Frame<R> {
      }

      // Values have no prototype chain, so `.constructor` resolves to the owning built-in directly.
-      if (operation === "read" && key === "constructor" && !hasOwn(objectValue, key)) {
+      if (
+        operation === "read" &&
+        key === "constructor" &&
+        !(objectValue instanceof ProgramObject && has(objectValue, key))
+      ) {
        const name = constructorName(objectValue)
        if (name !== undefined) return new ComputedValue(self.runtime.builtins.get(name))
      }
@@ -2136,6 +2168,8 @@ class Frame<R> {
        return new ComputedValue(undefined)
      }

+      if (objectValue instanceof ProgramObject) return { target: objectValue, key }
+
      if (isRuntimeReference(objectValue)) {
        throw new InterpreterRuntimeError(
          `Cannot read properties of ${describeValue(objectValue)}; only data values expose properties.`,
@@ -2143,42 +2177,27 @@ class Frame<R> {
          "InvalidDataValue",
        )
      }
-
-      if (typeof objectValue !== "object" || objectValue === null) {
-        throw new InterpreterRuntimeError("Cannot access a property on a non-object value.", objectNode)
-      }
-
-      if (Array.isArray(objectValue)) {
-        if (operation === "delete") return { target: objectValue, key }
-        const index = typeof key === "symbol" ? undefined : parseArrayIndex(key)
-        if (key !== "length" && !(typeof key === "string" && arrayMethods.has(key)) && index === undefined) {
-          if (typeof key === "string" && Object.hasOwn(objectValue, key)) {
-            return new ComputedValue((objectValue as Record<string, unknown> & Array<unknown>)[key])
-          }
-          return new ComputedValue(undefined)
-        }
-        return { target: objectValue, key: index ?? key }
-      }
-
-      return { target: objectValue as SafeObject, key }
+      throw new InterpreterRuntimeError("Cannot access a property on a non-object value.", objectNode)
    })
  }

  private readMember(node: MemberExpression): Effect.Effect<unknown, unknown, R> {
+    const self = this
    return Effect.map(this.getMemberReference(node), (reference) => {
      if (reference === OptionalShortCircuit) return OptionalShortCircuit
      if (reference instanceof ComputedValue) return reference.value
      if (reference === undefined || isOpaqueMemberReference(reference)) return reference
-      if (Array.isArray(reference.target)) {
-        if (reference.key === "length") return reference.target.length
-        if (typeof reference.key === "string") return new IntrinsicReference(reference.target, reference.key)
-        return Reflect.get(reference.target, reference.key)
+      const value = self.readReferenceValue(reference, reference.key)
+      if (
+        value === undefined &&
+        reference.target instanceof ProgramArray &&
+        typeof reference.key === "string" &&
+        arrayMethods.has(reference.key) &&
+        !has(reference.target, reference.key)
+      ) {
+        return new IntrinsicReference(reference.target, reference.key)
      }
-      if (reference.target instanceof Values.RegExp) return reference.target.lastIndex
-      if (reference.target instanceof Values.URL) {
-        return Reflect.get(reference.target.url, reference.key)
-      }
-      return Reflect.get(reference.target, reference.key)
+      return value
    })
  }

@@ -2204,7 +2223,7 @@ class Frame<R> {
      if (reference.target instanceof Values.RegExp) {
        return Reflect.deleteProperty(reference.target.regex, reference.key)
      }
-      return Reflect.deleteProperty(reference.target, reference.key)
+      return remove(reference.target, reference.key)
    })
  }

@@ -2224,12 +2243,6 @@ class Frame<R> {
      ) {
        throw new InterpreterRuntimeError("Only data fields may be assigned.", node)
      }
-      if (Array.isArray(reference.target)) {
-        if (reference.key === "length") throw new InterpreterRuntimeError("Array length cannot be assigned.", node)
-        if (typeof reference.key === "string" && arrayMethods.has(reference.key)) {
-          throw new InterpreterRuntimeError("Array methods cannot be assigned.", node)
-        }
-      }
      const key = reference.key
      const { write, next, result } = yield* compute(self.readReferenceValue(reference, key))
      if (write) self.assignToReference(reference, key, next, node)
@@ -2242,23 +2255,10 @@ class Frame<R> {
      return Reflect.get(reference.target.url, key)
    }
    if (reference.target instanceof Values.RegExp) return reference.target.lastIndex
-    return Reflect.get(reference.target, key)
+    return get(reference.target, key)
  }

  private assignToReference(reference: MemberReference, key: PropertyKey, next: unknown, node: AstNode): void {
-    if (Array.isArray(reference.target)) {
-      const target = reference.target
-      if (typeof key !== "number" || parseArrayIndex(key) === undefined) {
-        throw new InterpreterRuntimeError(
-          "Array assignment index must be a valid array index.",
-          node,
-          "InvalidDataValue",
-        )
-      }
-      rejectCircularInsertion(target, next, "Array assignment result", node)
-      target[key] = next
-      return
-    }
    if (reference.target instanceof Values.URL) {
      const property = key as string
      if (!urlWritableProperties.has(property)) {
@@ -2277,9 +2277,16 @@ class Frame<R> {
      reference.target.lastIndex = next
      return
    }
-    const target = reference.target as SafeObject
-    rejectCircularInsertion(target, next, "Object assignment result", node)
-    Reflect.set(target, key, next)
+    const target = reference.target
+    rejectCircularInsertion(
+      target,
+      next,
+      target instanceof ProgramArray ? "Array assignment result" : "Object assignment result",
+      node,
+    )
+    if (set(target, key, next)) return
+    if (target instanceof ProgramArray) throw new InterpreterRuntimeError("Invalid array length", node).as("RangeError")
+    throw new InterpreterRuntimeError(`Cannot assign to read only property '${String(key)}'.`, node).as("TypeError")
  }

  private toPropertyKey(value: unknown, node: AstNode): PropertyKey {
@@ -1,28 +1,27 @@
 import { Effect } from "effect"
 import { HostFunction, sync, syncCall } from "../interpreter/host.js"
 import { type AstNode, CodeModeGenerator, InterpreterRuntimeError } from "../interpreter/model.js"
+import { get, ProgramArray, ProgramObject } from "../interpreter/objects.js"
 import { describeValue } from "../interpreter/references.js"
 import { applyCollectionCallback, preserveConsumerError, type Runner } from "../interpreter/runner.js"

-const constructArray = (args: Array<unknown>, node: AstNode): Array<unknown> => {
-  if (args.length !== 1) return [...args]
+const constructArray = (args: Array<unknown>, node: AstNode): ProgramArray => {
+  if (args.length !== 1) return new ProgramArray([...args])
  const first = args[0]
-  if (typeof first !== "number") return [first]
+  if (typeof first !== "number") return new ProgramArray([first])
  if (!Number.isInteger(first) || first < 0 || first > 4294967295) {
    throw new InterpreterRuntimeError("Invalid array length.", node).as("RangeError")
  }
  // Sparse like JS: Array(3) has holes, and combinator loops already skip them.
-  return new Array(first)
+  return new ProgramArray(new Array(first))
 }

-const arrayLikeSource = (source: unknown, node: AstNode): { readonly length: number; readonly source: object } => {
-  if (
-    source !== null &&
-    typeof source === "object" &&
-    (Object.getPrototypeOf(source) === Object.prototype || Object.getPrototypeOf(source) === null) &&
-    typeof (source as { length?: unknown }).length === "number"
-  ) {
-    const length = (source as { length: number }).length
+const arrayLikeSource = (
+  source: unknown,
+  node: AstNode,
+): { readonly length: number; readonly source: ProgramObject } => {
+  if (source instanceof ProgramObject && typeof get(source, "length") === "number") {
+    const length = get(source, "length") as number
    const normalized = Number.isNaN(length) || length <= 0 ? 0 : Math.trunc(length)
    if (normalized > 4_294_967_295) throw new RangeError("Invalid array length")
    return { length: normalized, source }
@@ -49,16 +48,16 @@ const arrayFrom = <R>(runner: Runner<R>, args: Array<unknown>, node: AstNode): E
      const arrayLike = arrayLikeSource(source, node)
      const values: Array<unknown> = []
      for (let index = 0; index < arrayLike.length; index += 1) {
-        const item = Reflect.get(arrayLike.source, index)
+        const item = get(arrayLike.source, index)
        values.push(apply === undefined ? item : yield* apply([item, index]))
      }
-      return values
+      return new ProgramArray(values)
    }
    const values: Array<unknown> = []
    let index = 0
    while (true) {
      const step = yield* cursor.next
-      if (step.done) return values
+      if (step.done) return new ProgramArray(values)
      values.push(apply === undefined ? step.value : yield* preserveConsumerError(cursor, apply([step.value, index])))
      index += 1
    }
@@ -71,10 +70,10 @@ export const arrayGlobal = <R>(runner: Runner<R>) =>
    name: "Array",
    call: syncCall(constructArray),
    construct: syncCall(constructArray),
-    instanceOf: (value) => Array.isArray(value),
+    instanceOf: (value) => value instanceof ProgramArray,
    members: {
-      isArray: sync("Array.isArray", (args) => Array.isArray(args[0])),
-      of: sync("Array.of", (args) => [...args]),
+      isArray: sync("Array.isArray", (args) => args[0] instanceof ProgramArray),
+      of: sync("Array.of", (args) => new ProgramArray([...args])),
      from: new HostFunction<R>({ name: "Array.from", call: (args, node) => arrayFrom(runner, args, node) }),
    },
  })
@@ -1,7 +1,7 @@
 import { Effect } from "effect"
-import type { SafeObject } from "../data.js"
 import { HostFunction, requiresNew } from "../interpreter/host.js"
-import { type AstNode, InterpreterRuntimeError, isRecord } from "../interpreter/model.js"
+import { type AstNode, InterpreterRuntimeError } from "../interpreter/model.js"
+import { getOwn, ProgramArray, ProgramObject, set } from "../interpreter/objects.js"
 import { describeValue, isRuntimeReference } from "../interpreter/references.js"
 import { applyCollectionCallback, preserveConsumerError, type Runner, toPrimitive } from "../interpreter/runner.js"
 import { Values } from "../values.js"
@@ -108,13 +108,13 @@ export const groupBy = <R>(runner: Runner<R>, namespace: "Map" | "Object") =>
            const item = step.value
            const key = yield* preserveConsumerError(cursor, apply([item, index]))
            const group = result.map.get(key)
-            if (group === undefined) result.map.set(key, [item])
-            else (group as Array<unknown>).push(item)
+            if (group === undefined) result.map.set(key, new ProgramArray([item]))
+            else (group as ProgramArray).items.push(item)
            index += 1
          }
        }

-        const result: SafeObject = Object.create(null) as SafeObject
+        const result = new ProgramObject()
        let index = 0
        while (true) {
          const step = yield* cursor.next
@@ -124,9 +124,9 @@ export const groupBy = <R>(runner: Runner<R>, namespace: "Map" | "Object") =>
            cursor,
            Effect.flatMap(apply([item, index]), (value) => coerceGroupByPropertyKey(runner, value, node)),
          )
-          const group = result[key]
-          if (group === undefined) result[key] = [item]
-          else (group as Array<unknown>).push(item)
+          const group = getOwn(result, key)
+          if (group === undefined) set(result, key, new ProgramArray([item]))
+          else (group as ProgramArray).items.push(item)
          index += 1
        }
      })
@@ -150,12 +150,12 @@ const constructMap = <R>(runner: Runner<R>, init: unknown, node: AstNode) => {
      yield* preserveConsumerError(
        cursor,
        Effect.sync(() => {
-          if (!isRecord(step.value) || isRuntimeReference(step.value)) {
+          if (!(step.value instanceof ProgramObject)) {
            throw new InterpreterRuntimeError("new Map(...) expects [key, value] pairs as entry objects.", node).as(
              "TypeError",
            )
          }
-          target.map.set(step.value[0], step.value[1])
+          target.map.set(getOwn(step.value, 0), getOwn(step.value, 1))
        }),
      )
    }
@@ -1,5 +1,6 @@
 import { toData, toProgram } from "../data.js"
 import { HostNamespace, sync } from "../interpreter/host.js"
+import { get, ownEntries, ProgramArray, ProgramObject } from "../interpreter/objects.js"
 import { containsOpaqueReference, containsRuntimeReference, isRuntimeReference } from "../interpreter/references.js"
 import { Values } from "../values.js"
 import { coerceToString } from "./value.js"
@@ -51,8 +52,8 @@ const formatConsoleValue = (value: unknown, seen: Set<object>, depth: number): s
  if (value instanceof Values.Map) {
    seen.add(value)
    try {
-      const entries = Array.from(value.map.entries(), ([key, item]): Array<unknown> => [key, item])
-      return `Map(${value.map.size}) ${formatConsoleValue(entries, seen, depth + 1)}`
+      const entries = Array.from(value.map.entries(), ([key, item]) => new ProgramArray([key, item]))
+      return `Map(${value.map.size}) ${formatConsoleValue(new ProgramArray(entries), seen, depth + 1)}`
    } finally {
      seen.delete(value)
    }
@@ -60,7 +61,7 @@ const formatConsoleValue = (value: unknown, seen: Set<object>, depth: number): s
  if (value instanceof Values.Set) {
    seen.add(value)
    try {
-      return `Set(${value.set.size}) ${formatConsoleValue(Array.from(value.set.values()), seen, depth + 1)}`
+      return `Set(${value.set.size}) ${formatConsoleValue(new ProgramArray([...value.set.values()]), seen, depth + 1)}`
    } finally {
      seen.delete(value)
    }
@@ -68,10 +69,11 @@ const formatConsoleValue = (value: unknown, seen: Set<object>, depth: number): s
  if (isRuntimeReference(value)) return "[opaque reference]"
  seen.add(value)
  try {
-    if (Array.isArray(value)) {
-      return `[${value.map((item) => formatConsoleValue(item, seen, depth + 1)).join(",")}]`
+    if (value instanceof ProgramArray) {
+      return `[${value.items.map((item) => formatConsoleValue(item, seen, depth + 1)).join(",")}]`
    }
-    return `{${Object.entries(value)
+    if (!(value instanceof ProgramObject)) return "[object Object]"
+    return `{${ownEntries(value)
      .map(([key, item]) => `${JSON.stringify(key)}:${formatConsoleValue(item, seen, depth + 1)}`)
      .join(",")}}`
  } finally {
@@ -104,20 +106,19 @@ const consoleTableRows = (
  data: unknown,
  columns: ReadonlyArray<string> | undefined,
 ): Array<{ readonly index: string; readonly values: Record<string, unknown> }> => {
-  if (Array.isArray(data)) {
-    return data.map((item, index) => ({ index: String(index), values: consoleTableValues(item, columns) }))
+  if (data instanceof ProgramArray) {
+    return data.items.map((item, index) => ({ index: String(index), values: consoleTableValues(item, columns) }))
  }
-  if (data !== null && typeof data === "object" && !Values.isValue(data)) {
-    return Object.entries(data).map(([index, item]) => ({ index, values: consoleTableValues(item, columns) }))
+  if (data instanceof ProgramObject) {
+    return ownEntries(data).map(([index, item]) => ({ index, values: consoleTableValues(item, columns) }))
  }
  return [{ index: "0", values: { Value: data } }]
 }

 const consoleTableValues = (value: unknown, columns: ReadonlyArray<string> | undefined): Record<string, unknown> => {
-  if (value !== null && typeof value === "object" && !Array.isArray(value) && !Values.isValue(value)) {
-    const source = value as Record<string, unknown>
-    if (columns !== undefined) return Object.fromEntries(columns.map((column) => [column, source[column]]))
-    return Object.fromEntries(Object.entries(source))
+  if (value instanceof ProgramObject && !(value instanceof ProgramArray)) {
+    if (columns !== undefined) return Object.fromEntries(columns.map((column) => [column, get(value, column)]))
+    return Object.fromEntries(ownEntries(value))
  }
  return { Value: value }
 }
@@ -3,7 +3,8 @@ import { HostFunction, HostNamespace } from "../interpreter/host.js"
 import { applyCollectionCallback, type Runner } from "../interpreter/runner.js"
 import { type AstNode, InterpreterRuntimeError } from "../interpreter/model.js"
 import { typeofValue } from "../interpreter/references.js"
-import { fromData, type SafeObject, toData, toProgram } from "../data.js"
+import { fromData, toData, toProgram } from "../data.js"
+import { get, ownKeys, ProgramArray, ProgramObject, record, remove, set } from "../interpreter/objects.js"
 import { Values } from "../values.js"

 export const jsonGlobal = <R>(runner: Runner<R>) =>
@@ -29,28 +30,19 @@ const parse = <R>(runner: Runner<R>, args: Array<unknown>, node: AstNode): Effec
  if (typeofValue(args[1]) !== "function") return Effect.succeed(parsed)

  const apply = applyCollectionCallback(runner, args[1], "JSON.parse", node)
-  const root: SafeObject = Object.create(null) as SafeObject
-  root[""] = parsed
-  const visit = (holder: SafeObject | Array<unknown>, key: string): Effect.Effect<unknown, unknown, R> =>
+  const visit = (holder: ProgramObject, key: string): Effect.Effect<unknown, unknown, R> =>
    Effect.gen(function* () {
-      const value = holder[key as keyof typeof holder]
-      if (Array.isArray(value)) {
-        const length = value.length
-        for (let index = 0; index < length; index += 1) {
-          const revived = yield* visit(value, String(index))
-          if (revived === undefined) Reflect.deleteProperty(value, index)
-          else value[index] = revived
-        }
-      } else if (isPlainObject(value)) {
-        for (const name of Object.keys(value)) {
-          const revived = yield* visit(value, name)
-          if (revived === undefined) Reflect.deleteProperty(value, name)
-          else value[name] = revived
+      const value = get(holder, key)
+      if (value instanceof ProgramObject) {
+        for (const name of ownKeys(value)) {
+          const revived = yield* visit(value, name as string)
+          if (revived === undefined) remove(value, name)
+          else set(value, name, revived)
        }
      }
      return yield* apply([key, value])
    })
-  return visit(root, "")
+  return visit(record({ "": parsed }), "")
 }

 const stringify = <R>(runner: Runner<R>, args: Array<unknown>, node: AstNode): Effect.Effect<unknown, unknown, R> => {
@@ -59,44 +51,41 @@ const stringify = <R>(runner: Runner<R>, args: Array<unknown>, node: AstNode): E
  const replacer = args[1]

  if (typeofValue(replacer) !== "function") {
-    const properties = Array.isArray(replacer)
-      ? replacer
-          .filter((item): item is string | number => typeof item === "string" || typeof item === "number")
-          .map(String)
-      : null
+    const properties =
+      replacer instanceof ProgramArray
+        ? replacer.items
+            .filter((item): item is string | number => typeof item === "string" || typeof item === "number")
+            .map(String)
+        : null
    return Effect.succeed(JSON.stringify(toData(args[0], "JSON.stringify value"), properties, indent))
  }

  // Validate up front; the replacer walk below reads the original value.
  toProgram(args[0], "JSON.stringify value")
  const apply = applyCollectionCallback(runner, replacer, "JSON.stringify", node)
-  const root: SafeObject = Object.create(null) as SafeObject
-  root[""] = args[0]
  const stack = new Set<object>()
-  const visit = (holder: SafeObject | Array<unknown>, key: string): Effect.Effect<unknown, unknown, R> =>
+  const visit = (holder: ProgramObject, key: string): Effect.Effect<unknown, unknown, R> =>
    Effect.gen(function* () {
-      const value = yield* apply([key, toJSONValue(holder[key as keyof typeof holder])])
+      const value = yield* apply([key, toJSONValue(get(holder, key))])
      if (value === undefined || typeofValue(value) === "function") return undefined
      toProgram(value, "JSON.stringify replacer result")
      if (typeof value === "number") return Number.isFinite(value) ? value : null
      if (value === null || typeof value === "string" || typeof value === "boolean") return value
-      if (Array.isArray(value)) {
-        if (stack.has(value))
-          throw new InterpreterRuntimeError("Converting circular structure to JSON.", node).as("TypeError")
-        stack.add(value)
+      if (!(value instanceof ProgramObject)) return {}
+      if (stack.has(value))
+        throw new InterpreterRuntimeError("Converting circular structure to JSON.", node).as("TypeError")
+      stack.add(value)
+      if (value instanceof ProgramArray) {
        const result: Array<unknown> = []
-        for (let index = 0; index < value.length; index += 1) {
+        for (let index = 0; index < value.items.length; index += 1) {
          result.push((yield* visit(value, String(index))) ?? null)
        }
        stack.delete(value)
        return result
      }
-      if (!isPlainObject(value)) return {}
-      if (stack.has(value))
-        throw new InterpreterRuntimeError("Converting circular structure to JSON.", node).as("TypeError")
-      stack.add(value)
-      const result: SafeObject = Object.create(null) as SafeObject
-      for (const name of Object.keys(value)) {
+      const result: Record<string, unknown> = Object.create(null)
+      for (const name of ownKeys(value)) {
+        if (typeof name !== "string") continue
        const item = yield* visit(value, name)
        if (item !== undefined) result[name] = item
      }
@@ -104,7 +93,7 @@ const stringify = <R>(runner: Runner<R>, args: Array<unknown>, node: AstNode): E
      return result
    })

-  return Effect.map(visit(root, ""), (value) => JSON.stringify(value, null, indent))
+  return Effect.map(visit(record({ "": args[0] }), ""), (value) => JSON.stringify(value, null, indent))
 }

 const toJSONValue = (value: unknown): unknown => {
@@ -114,6 +103,3 @@ const toJSONValue = (value: unknown): unknown => {
  if (value instanceof Values.URL) return value.url.href
  return value
 }
-
-const isPlainObject = (value: unknown): value is SafeObject =>
-  value !== null && typeof value === "object" && !Values.isValue(value)
@@ -2,11 +2,10 @@ import { Effect } from "effect"
 import { toProgram } from "../data.js"
 import { HostFunction, sync, syncCall } from "../interpreter/host.js"
 import { type AstNode, AsyncIteratorSymbol, InterpreterRuntimeError, IteratorSymbol } from "../interpreter/model.js"
+import { getOwn, hasOwn, ownEntries, ownKeys, ProgramArray, ProgramObject, set } from "../interpreter/objects.js"
 import {
  containsOpaqueReference,
  describeValue,
-  isRuntimeReference,
-  parseArrayIndex,
  rejectCircularInsertion,
  typeofValue,
 } from "../interpreter/references.js"
@@ -16,9 +15,8 @@ import { Values } from "../values.js"
 import { groupBy } from "./collections.js"
 import { coerceToString } from "./value.js"

-// ToObject for enumeration. Strings return themselves: the host's Object.keys/entries/hasOwn index a
-// primitive string directly. Numbers, booleans, wrappers, and functions have no own enumerable keys.
-export const enumerableSource = (label: string, value: unknown, node: AstNode): Record<string, unknown> => {
+// ToObject for enumeration.
+export const enumerableSource = (label: string, value: unknown, node: AstNode): ProgramObject => {
  if (value === null || value === undefined) {
    throw new InterpreterRuntimeError(`${label} cannot convert ${describeValue(value)} to an object.`, node).as(
      "TypeError",
@@ -38,58 +36,41 @@ export const enumerableSource = (label: string, value: unknown, node: AstNode):
      "InvalidDataValue",
    )
  }
-  if (typeof value === "string") return value as unknown as Record<string, unknown>
-  if (typeof value !== "object" || Values.isValue(value) || isRuntimeReference(value)) return {}
-  return value as Record<string, unknown>
+  if (typeof value === "string") return new ProgramArray([...value])
+  if (value instanceof ProgramObject) return value
+  return new ProgramObject()
 }

 export const objectAssign = (args: Array<unknown>, node: AstNode): unknown => {
  const target = args[0]
  // JS would box a primitive target; wrappers and primitives cannot hold fields here.
-  if (target === null || typeof target !== "object" || Values.isValue(target) || isRuntimeReference(target)) {
+  if (!(target instanceof ProgramObject)) {
    throw new InterpreterRuntimeError(
      `Object.assign expects a data object or array target, received ${describeValue(target)}.`,
      node,
    ).as("TypeError")
  }
-  const out = target as Record<string, unknown>
  const seen = new Set<object>()
-  const guardedSet = (key: PropertyKey, item: unknown): void => {
-    // Arrays hold only indexed elements, as with direct assignment; Reflect.set would otherwise
-    // reach Array's length and Object.prototype's __proto__ setter.
-    if (Array.isArray(out) && (typeof key === "symbol" || parseArrayIndex(key) === undefined)) {
-      throw new InterpreterRuntimeError(
-        `Object.assign cannot assign '${String(key)}' to an array: only array indexes may be assigned.`,
-        node,
-      ).as("TypeError")
-    }
-    rejectCircularInsertion(out, item, "Object.assign result", node, seen)
-    if (!Reflect.set(out, key, item))
-      throw new InterpreterRuntimeError(`Object.assign could not assign property '${String(key)}'.`, node).as(
-        "TypeError",
-      )
-  }
  for (const source of args.slice(1)) {
    if (source === null || source === undefined) continue
    const from = enumerableSource("Object.assign(...)", source, node)
-    if (typeof from !== "object") {
-      for (const [key, item] of Object.entries(from)) guardedSet(key, item)
-      continue
-    }
-    for (const key of Reflect.ownKeys(from)) {
+    for (const key of ownKeys(from)) {
      if (typeof key === "symbol" && key !== AsyncIteratorSymbol && key !== IteratorSymbol) continue
-      if (Object.prototype.propertyIsEnumerable.call(from, key)) guardedSet(key, Reflect.get(from, key))
+      rejectCircularInsertion(target, getOwn(from, key), "Object.assign result", node, seen)
+      if (!set(target, key, getOwn(from, key))) {
+        throw new InterpreterRuntimeError("Invalid array length", node).as("RangeError")
+      }
    }
  }
-  return out
+  return target
 }

 const objectFromEntries = <R>(
  runner: Runner<R>,
  source: unknown,
  node: AstNode,
-): Effect.Effect<Record<string, unknown>, unknown, R> => {
-  const out: Record<string, unknown> = Object.create(null)
+): Effect.Effect<ProgramObject, unknown, R> => {
+  const out = new ProgramObject()
  return Effect.gen(function* () {
    const cursor = yield* runner.syncIterator(source, node)
    if (cursor === undefined) {
@@ -103,21 +84,12 @@ const objectFromEntries = <R>(
      yield* preserveConsumerError(
        cursor,
        Effect.sync(() => {
-          if (
-            step.value === null ||
-            typeof step.value !== "object" ||
-            Values.isValue(step.value) ||
-            containsOpaqueReference(step.value)
-          ) {
+          if (!(step.value instanceof ProgramObject) || containsOpaqueReference(step.value)) {
            throw new InterpreterRuntimeError("Object.fromEntries expects [key, value] entry objects.", node).as(
              "TypeError",
            )
          }
-          const entry = step.value as Record<string, unknown>
-          toProgram(entry[0], "Object.fromEntries key")
-          toProgram(entry[1], "Object.fromEntries value")
-          const key = coerceToString(entry[0])
-          out[key] = entry[1]
+          set(out, coerceToString(getOwn(step.value, 0)), getOwn(step.value, 1))
        }),
      )
    }
@@ -126,7 +98,7 @@ const objectFromEntries = <R>(

 const constructObject = (args: Array<unknown>, node: AstNode): unknown => {
  const first = args[0]
-  if (first === null || first === undefined) return Object.create(null)
+  if (first === null || first === undefined) return new ProgramObject()
  if (typeof first === "object") return first
  throw new InterpreterRuntimeError(
    `Object(${typeof first}) wrapper objects are not supported; use the primitive value directly.`,
@@ -147,18 +119,24 @@ export const objectGlobal = <R>(runner: Runner<R>, toolKeys: (path: ReadonlyArra
        toProgram(
          args[0] instanceof ToolReference
            ? [...toolKeys(args[0].path)]
-            : Object.keys(enumerableSource("Object.keys(...)", args[0], node)),
+            : ownKeys(enumerableSource("Object.keys(...)", args[0], node)).filter((key) => typeof key === "string"),
          "Object.keys result",
        ),
      ),
-      values: sync("Object.values", (args, node) =>
-        Object.values(enumerableSource("Object.values(...)", args[0], node)),
+      values: sync(
+        "Object.values",
+        (args, node) =>
+          new ProgramArray(ownEntries(enumerableSource("Object.values(...)", args[0], node)).map((entry) => entry[1])),
      ),
-      entries: sync("Object.entries", (args, node) =>
-        Object.entries(enumerableSource("Object.entries(...)", args[0], node)).map(([key, item]) => [key, item]),
+      entries: sync(
+        "Object.entries",
+        (args, node) =>
+          new ProgramArray(
+            ownEntries(enumerableSource("Object.entries(...)", args[0], node)).map((entry) => new ProgramArray(entry)),
+          ),
      ),
      hasOwn: sync("Object.hasOwn", (args, node) =>
-        Object.hasOwn(
+        hasOwn(
          enumerableSource("Object.hasOwn(...)", args[0], node),
          args[1] === AsyncIteratorSymbol || args[1] === IteratorSymbol ? args[1] : String(args[1]),
        ),
@@ -1,19 +1,9 @@
 import { sync, syncCall } from "../interpreter/host.js"
 import { type AstNode, InterpreterRuntimeError } from "../interpreter/model.js"
-import type { SafeObject } from "../data.js"
+import { ProgramArray, record, set } from "../interpreter/objects.js"
 import { Values } from "../values.js"
 import { coerceToNumber, coerceToString } from "./value.js"

-type MatchValue = Array<unknown> & {
-  index?: number
-  groups?: SafeObject
-  indices?: IndicesValue
-}
-
-type IndicesValue = Array<unknown> & {
-  groups?: SafeObject
-}
-
 export const regexpMethods = new Set(["test", "exec", "toString"])

 export const regexpProperties = new Set([
@@ -56,17 +46,12 @@ export const toHostRegex = (arg: unknown, method: string, node: AstNode, extraFl
  )
 }

-export const matchToValue = (match: RegExpMatchArray): Array<unknown> => {
-  const result: MatchValue = Array.from(match, (group) => group)
-  if (match.index !== undefined) result.index = match.index
-  if (match.groups) {
-    const groups: SafeObject = Object.create(null) as SafeObject
-    for (const [key, group] of Object.entries(match.groups)) {
-      groups[key] = group
-    }
-    result.groups = groups
-  }
-  if (match.indices) result.indices = indicesToValue(match.indices)
+export const matchToValue = (match: RegExpMatchArray): ProgramArray => {
+  const result = new ProgramArray(Array.from(match, (group) => group))
+  if (match.index !== undefined) set(result, "index", match.index)
+  if (match.input !== undefined) set(result, "input", match.input)
+  if (match.groups) set(result, "groups", record(match.groups))
+  if (match.indices) set(result, "indices", indicesToValue(match.indices))
  return result
 }

@@ -143,16 +128,16 @@ const toLength = (value: unknown): number => {
  return Math.min(Math.floor(number), Number.MAX_SAFE_INTEGER)
 }

-const indicesToValue = (indices: RegExpIndicesArray): IndicesValue => {
-  const result: IndicesValue = Array.from(indices, (range) => (range === undefined ? undefined : [...range]))
-  if (indices.groups) {
-    const groups: SafeObject = Object.create(null) as SafeObject
-    for (const [key, range] of Object.entries(indices.groups)) {
-      groups[key] = range === undefined ? undefined : [...range]
-    }
-    result.groups = groups
-    return result
-  }
-  result.groups = undefined
+const indicesToValue = (indices: RegExpIndicesArray): ProgramArray => {
+  const range = (pair: [number, number] | undefined) => (pair === undefined ? undefined : new ProgramArray([...pair]))
+  const result = new ProgramArray(Array.from(indices, range))
+  const groups = indices.groups
+  set(
+    result,
+    "groups",
+    groups === undefined
+      ? undefined
+      : record(Object.fromEntries(Object.entries(groups).map(([key, pair]) => [key, range(pair)]))),
+  )
  return result
 }
@@ -2,6 +2,7 @@ import { Effect } from "effect"
 import { toProgram } from "../data.js"
 import { HostFunction, requiresNew, sync, syncCall } from "../interpreter/host.js"
 import { type AstNode, InterpreterRuntimeError } from "../interpreter/model.js"
+import { ownEntries, ProgramObject } from "../interpreter/objects.js"
 import { isRuntimeReference } from "../interpreter/references.js"
 import { preserveConsumerError, type Runner } from "../interpreter/runner.js"
 import { Values } from "../values.js"
@@ -183,15 +184,14 @@ const constructURLSearchParams = <R>(
      ).as("TypeError")
    }
    if (Values.isValue(init)) return new Values.URLSearchParams(new URLSearchParams())
-    const data = toProgram(init, "new URLSearchParams input")
-    if (data === null || typeof data !== "object") {
+    if (!(init instanceof ProgramObject)) {
      throw new InterpreterRuntimeError(
        "new URLSearchParams(...) expects a query string, data object, iterable pairs, or URLSearchParams.",
        node,
      ).as("TypeError")
    }
    return new Values.URLSearchParams(
-      new URLSearchParams(Object.fromEntries(Object.entries(data).map(([key, value]) => [key, coerceToString(value)]))),
+      new URLSearchParams(Object.fromEntries(ownEntries(init).map(([key, value]) => [key, coerceToString(value)]))),
    )
  })
 }
@@ -1,6 +1,7 @@
 import { type HostFunction, sync, type SyncOptions } from "../interpreter/host.js"
 import { type AstNode, InterpreterRuntimeError } from "../interpreter/model.js"
-import { type SafeObject, toProgram } from "../data.js"
+import { toProgram } from "../data.js"
+import { get, ProgramArray, ProgramError, set } from "../interpreter/objects.js"
 import { Values } from "../values.js"

 export const errorConstructors = new Set([
@@ -16,21 +17,21 @@ export const errorConstructors = new Set([

 export const compoundOperators = new Set(["+=", "-=", "*=", "/=", "%=", "**=", "&=", "|=", "^=", "<<=", ">>=", ">>>="])

-const ErrorBrand: unique symbol = Symbol("codemode.error")
-
-export const createErrorValue = (name: string, message: string): SafeObject => {
-  const value = Object.assign(Object.create(null) as SafeObject, { name, message })
-  Object.defineProperty(value, ErrorBrand, { value: name })
+export const createErrorValue = (name: string, message: string): ProgramError => {
+  const value = new ProgramError(name)
+  set(value, "name", name)
+  set(value, "message", message)
  return value
 }

-export const createAggregateErrorValue = (errors: Array<unknown>, message: string): SafeObject =>
-  Object.assign(createErrorValue("AggregateError", message), { errors })
+export const createAggregateErrorValue = (errors: Array<unknown>, message: string): ProgramError => {
+  const value = createErrorValue("AggregateError", message)
+  set(value, "errors", new ProgramArray(errors))
+  return value
+}

 export const errorBrandName = (value: unknown): string | undefined =>
-  value !== null && typeof value === "object"
-    ? ((value as Record<PropertyKey, unknown>)[ErrorBrand] as string | undefined)
-    : undefined
+  value instanceof ProgramError ? value.errorName : undefined

 export const coerceToString = (value: unknown): string => {
  if (value === null) return "null"
@@ -42,29 +43,27 @@ export const coerceToString = (value: unknown): string => {
  if (value instanceof Values.Set) return "[object Set]"
  if (value instanceof Values.URL) return value.url.href
  if (value instanceof Values.URLSearchParams) return value.params.toString()
-  if (errorBrandName(value) !== undefined) {
+  if (value instanceof ProgramError) {
    // Match Error.prototype.toString: "name: message", or just one when the other is empty.
-    const error = value as { name?: unknown; message?: unknown }
-    const name = typeof error.name === "string" ? error.name : "Error"
-    const message = typeof error.message === "string" ? error.message : ""
-    if (message === "") return name
-    if (name === "") return message
-    return `${name}: ${message}`
+    const name = get(value, "name")
+    const message = get(value, "message")
+    const shownName = typeof name === "string" ? name : "Error"
+    const shownMessage = typeof message === "string" ? message : ""
+    if (shownMessage === "") return shownName
+    if (shownName === "") return shownMessage
+    return `${shownName}: ${shownMessage}`
  }
-  if (typeof value === "object") {
-    return Array.isArray(value)
-      ? value.map((item) => (item === null || item === undefined ? "" : coerceToString(item))).join(",")
-      : "[object Object]"
+  if (value instanceof ProgramArray) {
+    return value.items.map((item) => (item === null || item === undefined ? "" : coerceToString(item))).join(",")
  }
+  if (typeof value === "object") return "[object Object]"
  return String(value)
 }

 export const coerceToNumber = (value: unknown): number => {
  if (value instanceof Values.Date) return value.time
  if (Values.isValue(value)) return Number.NaN
-  // Arrays coerce through our own string coercion: host Number(array) joins with host
-  // ToPrimitive, which throws on the null-prototype objects the interpreter produces.
-  if (Array.isArray(value)) return Number(coerceToString(value))
+  if (value instanceof ProgramArray) return Number(coerceToString(value))
  return value !== null && typeof value === "object" ? Number.NaN : Number(value)
 }

@@ -78,8 +77,6 @@ const coerce = (name: Coercion, args: Array<unknown>, node: AstNode): unknown =>
    if (name === "String") return ""
  }
  const raw = args[0]
-  // Error values are plain SafeObjects; the toProgram path below would strip their brand.
-  if (name === "String" && errorBrandName(raw) !== undefined) return coerceToString(raw)
  if (Values.isValue(raw)) {
    if (name === "Boolean") return true
    if (name === "Number") return coerceToNumber(raw)
@@ -98,7 +98,7 @@ describe("Object.keys over arrays", () => {
    )
    expect((await error(`const { a } = new Map(); return a`)).message).toContain("received a Map.")
    expect((await error(`return Array.from(7)`)).message).toContain("received a number.")
-    expect((await error(`return (() => 1).x`)).message).toContain("Cannot read properties of a function")
+    expect(await value(`return [(() => 1).x, Object.keys(() => 1)]`)).toEqual([null, []])
  })
 })

@@ -167,17 +167,14 @@ describe("Object.assign Test262 parity", () => {
    ).toEqual([true, [1, 8, 9], true, [1, 8, 3], true, 5, true, 0])
  })

-  test("array targets accept only array indexes (deviation from target-Array.js)", async () => {
+  test("test/built-ins/Object/assign/target-Array.js", async () => {
    expect(
      await value(`
        const target = [7]
-        const out = []
-        for (const source of [{ length: 0 }, { x: 1 }, { "1.5": 1 }, { "-0": 1 }, { ["__proto__"]: null }]) {
-          try { Object.assign(target, source) } catch (error) { out.push(error.name) }
-        }
-        return [out, [...target], target.length, Object.keys(target)]
+        for (const source of [{ x: 1 }, { "1.5": 1 }, { "-0": 1 }, { 1: 8 }, { length: 1 }]) Object.assign(target, source)
+        return [[...target], target.length, Object.keys(target), target.x]
      `),
-    ).toEqual([["TypeError", "TypeError", "TypeError", "TypeError", "TypeError"], [7], 1, ["0"]])
+    ).toEqual([[7], 1, ["0", "x", "1.5", "-0"], 1])
  })

  test("test/built-ins/Object/assign/Target-{Null,Undefined}.js", async () => {
@@ -81,27 +81,26 @@ describe("H3: array property access reads as undefined (not a throw)", () => {
    ).toEqual(["b", "b", null, null, "a", null])
  })

-  test("noncanonical keys cannot mutate or delete an aliased element", async () => {
+  test("noncanonical keys are ordinary properties that never alias an element", async () => {
    expect(
      await value(`
        const values = ["a", "b"]
-        let writes = 0
-        try { values["01"] = ++writes } catch {}
+        values["01"] = "c"
+        const before = [values["01"], values[1], values.length]
        const removed = delete values["01"]
-        return [writes, removed, values]
+        return [before, removed, values["01"], values]
      `),
-    ).toEqual([0, true, ["a", "b"]])
+    ).toEqual([["c", "b", 2], true, null, ["a", "b"]])
  })

-  test("the maximum array length is not accepted as an array index", async () => {
+  test("the maximum array length is a property, not an index", async () => {
    expect(
      await value(`
        const values = []
-        let writes = 0
-        try { values["4294967295"] = ++writes } catch {}
-        return [writes, values.length]
+        values["4294967295"] = 1
+        return [values["4294967295"], values.length]
      `),
-    ).toEqual([0, 0])
+    ).toEqual([1, 0])
  })
 })

@@ -246,16 +245,14 @@ describe("property deletion", () => {
    expect(await value(`const values = [1, 2]; return [delete values.length, values.length]`)).toEqual([false, 2])
  })

-  test("does not broaden unsupported array property assignment", async () => {
+  test("arrays accept named properties like JS, and they stay out of the JSON form", async () => {
    expect(
      await value(`
-        const values = []
-        let rightHandSideRuns = 0
-        function next() { rightHandSideRuns++; return 1 }
-        try { values.field = next() } catch {}
-        return rightHandSideRuns
+        const values = [1]
+        values.field = 2
+        return [values.field, Object.keys(values), values]
      `),
-    ).toBe(0)
+    ).toEqual([2, ["0", "field"], [1]])
  })

  test("optional deletion short-circuits without evaluating the key", async () => {
@@ -916,3 +913,48 @@ describe("coercion parity: unknown static members read as undefined", () => {
    ])
  })
 })
+
+describe("functions are objects", () => {
+  test("name follows NamedEvaluation and length counts required parameters", async () => {
+    expect(
+      await value(`
+        function decl(a, b = 1, ...rest) {}
+        const arrow = () => {}
+        const named = function inner() {}
+        let assigned
+        assigned = (a, b) => {}
+        const { fromDefault = () => {} } = {}
+        const [fromArray = function () {}] = []
+        const obj = { method() {}, key: () => {}, [Symbol.iterator]: () => {} }
+        const passthrough = (0, () => {})
+        return [
+          [decl.name, decl.length],
+          [arrow.name, named.name, assigned.name, assigned.length],
+          [fromDefault.name, fromArray.name],
+          [obj.method.name, obj.key.name, obj[Symbol.iterator].name],
+          passthrough.name,
+        ]
+      `),
+    ).toEqual([
+      ["decl", 1],
+      ["arrow", "inner", "assigned", 2],
+      ["fromDefault", "fromArray"],
+      ["method", "key", "[Symbol.iterator]"],
+      "",
+    ])
+  })
+
+  test("functions hold own properties; name and length are read-only", async () => {
+    expect(
+      await value(`
+        const fn = () => 1
+        fn.count = 2
+        fn.count += 1
+        let renamed = false
+        try { fn.name = "other" } catch (error) { renamed = error instanceof TypeError }
+        const { name, count } = fn
+        return [fn.count, Object.keys(fn), "count" in fn, "name" in fn, name, count, renamed, delete fn.count, fn.count]
+      `),
+    ).toEqual([3, ["count"], true, true, "fn", 3, true, true, null])
+  })
+})
@@ -17,8 +17,6 @@
 import { describe, expect, test } from "bun:test"
 import { Effect, Schema } from "effect"
 import { CodeMode, Tool } from "../src/index.js"
-import { AsyncIteratorSymbol, IteratorSymbol } from "../src/interpreter/model.js"
-import { objectAssign } from "../src/stdlib/object.js"

 // Standard-library value types: Date, RegExp, Map, Set. Programs use them as ordinary JS;
 // intra-CodeMode checkpoints (Object.* helpers, spread, coercion inputs) preserve the live
@@ -770,13 +768,18 @@ describe("stdlib integration", () => {
      ],
    ])
    expect(await value(`const match = /a/.exec("ba"); return [Object.values(match), Object.entries(match)]`)).toEqual([
-      ["a", 1],
+      ["a", 1, "ba"],
      [
        ["0", "a"],
        ["index", 1],
+        ["input", "ba"],
      ],
    ])
-    expect(await value(`return Object.keys(Object.values({ match: /a/.exec("ba") })[0])`)).toEqual(["0", "index"])
+    expect(await value(`return Object.keys(Object.values({ match: /a/.exec("ba") })[0])`)).toEqual([
+      "0",
+      "index",
+      "input",
+    ])
  })

  test("Object.fromEntries accepts every supported entry collection", async () => {
@@ -849,86 +852,6 @@ describe("stdlib integration", () => {
    expect(await value(`try { Object.assign(null, { a: 1 }); return false } catch { return true }`)).toBe(true)
  })

-  test("Object.assign ignores non-enumerable supported symbols without reading them", () => {
-    const target = {}
-    const reads: Array<boolean> = []
-    const source = Object.defineProperty({}, IteratorSymbol, {
-      get() {
-        reads.push(true)
-        return target
-      },
-    })
-    expect(objectAssign([target, source], { type: "CallExpression", start: 0, end: 0 })).toBe(target)
-    expect(reads).toEqual([])
-    expect(Object.hasOwn(target, IteratorSymbol)).toBe(false)
-  })
-
-  test("Object.assign ignores nested non-enumerable supported symbols during cycle checks", () => {
-    const target = {}
-    const reads: Array<boolean> = []
-    const nested = Object.defineProperty({}, IteratorSymbol, {
-      get() {
-        reads.push(true)
-        return target
-      },
-    })
-    expect(objectAssign([target, { nested }], { type: "CallExpression", start: 0, end: 0 })).toBe(target)
-    expect(reads).toEqual([])
-    expect(target).toEqual({ nested })
-  })
-
-  test("Object.assign rejects cycles through supported symbols on nested arrays", () => {
-    const target = {}
-    const nested = Object.defineProperty([], IteratorSymbol, { enumerable: true, value: target })
-    expect(() => objectAssign([target, { nested }], { type: "CallExpression", start: 0, end: 0 })).toThrow(
-      "Object.assign result contains a circular value.",
-    )
-    expect(Object.hasOwn(target, "nested")).toBe(false)
-  })
-
-  test("Object.assign cycle checks traverse sparse keys lazily", () => {
-    const target = {}
-    const reads: Array<boolean> = []
-    const nested = Object.defineProperties([], {
-      4294967294: { enumerable: true, value: target },
-      later: {
-        enumerable: true,
-        get() {
-          reads.push(true)
-          return null
-        },
-      },
-    })
-    expect(() => objectAssign([target, { nested }], { type: "CallExpression", start: 0, end: 0 })).toThrow(
-      "Object.assign result contains a circular value.",
-    )
-    expect(reads).toEqual([])
-  })
-
-  test("Object.assign stops after a supported symbol write fails", () => {
-    const previous = () => ({ done: true })
-    const target = Object.defineProperty({}, IteratorSymbol, { value: previous })
-    const reads: Array<boolean> = []
-    const source = Object.defineProperties(
-      {},
-      {
-        [IteratorSymbol]: { enumerable: true, value: () => ({ done: false }) },
-        [AsyncIteratorSymbol]: {
-          enumerable: true,
-          get() {
-            reads.push(true)
-            return () => ({ done: true })
-          },
-        },
-      },
-    )
-    expect(() => objectAssign([target, source], { type: "CallExpression", start: 0, end: 0 })).toThrow(
-      "Object.assign could not assign property",
-    )
-    expect(Reflect.get(target, IteratorSymbol)).toBe(previous)
-    expect(reads).toEqual([])
-  })
-
  test("Object.assign rejects direct and nested cycles", async () => {
    expect(
      await value(`
@@ -1000,27 +923,6 @@ describe("stdlib integration", () => {
    ).toEqual([true, true, true, 2])
  })

-  test("Object.assign traverses shared aliases once", () => {
-    const reads: Array<boolean> = []
-    const shared = Object.defineProperty({}, "value", {
-      enumerable: true,
-      get() {
-        reads.push(true)
-        return 1
-      },
-    })
-    const target = {}
-    expect(
-      objectAssign([target, { left: shared, right: shared }], {
-        type: "CallExpression",
-        start: 0,
-        end: 0,
-      }),
-    ).toBe(target)
-    expect(target).toEqual({ left: shared, right: shared })
-    expect(reads).toEqual([true])
-  })
-
  test("assignment resolves and reads its left side before evaluating the right side", async () => {
    expect(await value(`let x = 1; x += (x = 5); return x`)).toBe(6)
    expect(await value(`let i = 0; const values = [9]; values[i++] = i; return [values, i]`)).toEqual([[1], 1])
@@ -1199,7 +1101,7 @@ describe("CodeMode values at intra-CodeMode checkpoints", () => {
    const diagnostic = await error(`return Array.from(Promise.resolve([1]))`)
    expect(diagnostic.kind).toBe("InvalidDataValue")
    expect(diagnostic.message).toContain("await")
-    expect((await error(`return Array.from(() => 1)`)).kind).toBe("InvalidDataValue")
+    expect(await value(`return Array.from((a, b) => 1)`)).toEqual([null, null])
  })

  test("regexes stay callable through Object.values", async () => {
@@ -0,0 +1,20 @@
+/*
+ * Runs the test262 files vendored under test/test262 (see test/test262/README.md) verbatim.
+ * Files listed in test/test262/skipped.txt fail on a known interpreter gap and are skipped;
+ * `bun run script/test262-report.ts` shows current gaps and which skipped files pass again.
+ * Licensed under test/LICENSE.test262.
+ */
+import { test } from "bun:test"
+import { root, run, skipped } from "./test262/run.js"
+
+for (const file of [...new Bun.Glob("**/*.js").scanSync({ cwd: root })].sort()) {
+  const define = skipped.has(file) ? test.skip : test
+  define(
+    file,
+    async () => {
+      const outcome = await run(file)
+      if (outcome.status === "fail") throw new Error(outcome.reason)
+    },
+    10_000,
+  )
+}
@@ -0,0 +1,3 @@
+# Upstream test262 files are populated locally by script/sync-test262.ts and not committed yet.
+built-ins/
+language/
@@ -0,0 +1,41 @@
+# test262
+
+Runs upstream [test262](https://github.com/tc39/test262) files verbatim through `test/test262.test.ts`. The files
+themselves are not committed yet: populate them from a local checkout with
+
+```sh
+git clone https://github.com/tc39/test262 ~/development/test262
+bun run script/sync-test262.ts ~/development/test262
+```
+
+Without them the runner registers no tests, so CI is unaffected. Licensed under `test/LICENSE.test262`.
+
+## Layout
+
+- `manifest.json` — the pinned upstream revision, which upstream directories are copied, and what is left out.
+- `built-ins/`, `language/` — the copied files, mirroring upstream `test/`; gitignored.
+- `skipped.txt` — vendored files that fail on a known interpreter gap, one `path  # reason` per line. They are
+  skipped, and each gap is listed as unchecked in `interpreter-support.md`.
+- `run.ts` — runs one file: prepends `"use strict"`, provides the harness (`assert`, `Test262Error`,
+  `compareArray`, `$DONE`, `$DONOTEVALUATE`) as host globals, and interprets the file's frontmatter (`negative`,
+  `flags: [async]`).
+
+## What is not vendored
+
+`script/sync-test262.ts` skips a file when its frontmatter declares a `flags`, `features`, or `includes` value the
+manifest marks unsupported, or when its code matches one of the manifest's `boundaries` patterns. The sync checks the
+checkout is at the pinned revision, so every machine runs the same 3993 files. Boundaries are
+intentional limits of the interpreter, not compatibility work: classes, `this`, `arguments`, prototype objects,
+property descriptors, accessors, boxed primitives, sloppy mode, `eval`, `Symbol()`, and the `$262` host API. If one
+of those decisions changes, delete its entry and re-sync; the tests are upstream, not lost.
+
+## Commands
+
+```sh
+bun run script/sync-test262.ts /path/to/test262   # re-copy at the pinned revision; edit manifest.json to change scope
+bun run script/test262-report.ts [--write] [dir]  # run everything, group failures by cause; --write regenerates skipped.txt
+bun test test/test262.test.ts                     # what CI runs
+```
+
+When a fix makes skipped files pass, the report lists them so they can be removed from `skipped.txt`, and the
+matching gap in `interpreter-support.md` is checked in the same change.
@@ -0,0 +1,107 @@
+{
+  "revision": "250f204f23a9249ff204be2baec29600faae7b75",
+  "directories": ["built-ins/Array/prototype", "language/statements"],
+  "harness": ["assert.js", "sta.js", "compareArray.js", "doneprintHandle.js"],
+  "flags": ["module", "raw", "noStrict"],
+  "boundaries": {
+    "class": "\\bclass\\s*[A-Za-z_${]",
+    "this": "\\bthis\\b",
+    "arguments": "\\barguments\\b",
+    "call/apply/bind": "\\.(call|apply|bind)\\s*\\(",
+    "prototype objects": "\\.prototype\\b",
+    "accessor properties": "\\b(get|set)\\s+[\\w$\\[][^\\n(]*\\(",
+    "property descriptors": "Object\\.(defineProperty|defineProperties|getOwnPropertyDescriptors?|getOwnPropertyNames|create|getPrototypeOf|setPrototypeOf|freeze|seal|preventExtensions|isFrozen|isSealed|isExtensible)\\b",
+    "boxed primitives": "\\bnew\\s+(String|Number|Boolean)\\s*\\(",
+    "sloppy mode": "\\bwith\\s*\\(",
+    "eval": "\\b(eval|Function)\\b",
+    "new.target": "\\bnew\\.target\\b",
+    "globalThis": "\\bglobalThis\\b",
+    "Symbol": "\\bSymbol\\b(?!\\.(iterator|asyncIterator)\\b)",
+    "$262 host API": "\\$262"
+  },
+  "features": [
+    "BigInt",
+    "Proxy",
+    "proxy-missing-checks",
+    "Reflect",
+    "Reflect.construct",
+    "Reflect.set",
+    "Reflect.setPrototypeOf",
+    "Symbol",
+    "Symbol.hasInstance",
+    "Symbol.isConcatSpreadable",
+    "Symbol.match",
+    "Symbol.matchAll",
+    "Symbol.prototype.description",
+    "Symbol.replace",
+    "Symbol.search",
+    "Symbol.species",
+    "Symbol.split",
+    "Symbol.toPrimitive",
+    "Symbol.toStringTag",
+    "Symbol.unscopables",
+    "symbols-as-weakmap-keys",
+    "class",
+    "class-fields-private",
+    "class-fields-private-in",
+    "class-fields-public",
+    "class-methods-private",
+    "class-static-block",
+    "class-static-fields-private",
+    "class-static-fields-public",
+    "class-static-methods-private",
+    "super",
+    "new.target",
+    "decorators",
+    "TypedArray",
+    "TypedArray.prototype.at",
+    "ArrayBuffer",
+    "SharedArrayBuffer",
+    "DataView",
+    "Atomics",
+    "Atomics.pause",
+    "Atomics.waitAsync",
+    "resizable-arraybuffer",
+    "arraybuffer-transfer",
+    "immutable-arraybuffer",
+    "Float16Array",
+    "Float32Array",
+    "Float64Array",
+    "Int8Array",
+    "Int16Array",
+    "Int32Array",
+    "Uint8Array",
+    "Uint8ClampedArray",
+    "Uint16Array",
+    "Uint32Array",
+    "uint8array-base64",
+    "WeakMap",
+    "WeakSet",
+    "WeakRef",
+    "FinalizationRegistry",
+    "Intl-enumeration",
+    "Temporal",
+    "ShadowRealm",
+    "cross-realm",
+    "dynamic-import",
+    "import.meta",
+    "import-attributes",
+    "import-defer",
+    "export-defer",
+    "source-phase-imports",
+    "source-phase-imports-module-source",
+    "import-text",
+    "import-bytes",
+    "json-modules",
+    "top-level-await",
+    "explicit-resource-management",
+    "tail-call-optimization",
+    "caller",
+    "IsHTMLDDA",
+    "host-gc-required",
+    "legacy-regexp",
+    "__proto__",
+    "__getter__",
+    "__setter__"
+  ]
+}
@@ -0,0 +1,166 @@
+// Runs one vendored test262 file verbatim. The harness (assert, Test262Error, compareArray, $DONE,
+// $DONOTEVALUATE) is host-provided because programs cannot attach properties to functions, which
+// test262's own assert.js relies on.
+import path from "node:path"
+import { Cause, Effect } from "effect"
+import { caughtErrorValue } from "../../src/interpreter/errors.js"
+import { executeProgram } from "../../src/interpreter/execute.js"
+import type { Host } from "../../src/interpreter/globals.js"
+import { HostFunction } from "../../src/interpreter/host.js"
+import { ProgramThrow } from "../../src/interpreter/model.js"
+import { get, ProgramArray, ProgramObject } from "../../src/interpreter/objects.js"
+import { createErrorValue, errorBrandName } from "../../src/stdlib/value.js"
+import { ToolRuntime } from "../../src/tool-runtime.js"
+
+export const root = import.meta.dir
+
+/** Files that fail on a known gap, mapped to the gap; see skipped.txt. */
+export const skipped = new Map(
+  (await Bun.file(path.join(root, "skipped.txt")).text())
+    .split("\n")
+    .filter((line) => line.includes("#"))
+    .map((line) => [line.slice(0, line.indexOf("#")).trim(), line.slice(line.indexOf("#") + 1).trim()]),
+)
+
+export type Outcome = { readonly status: "pass" } | { readonly status: "fail"; readonly reason: string }
+
+type Frontmatter = {
+  flags?: Array<string>
+  negative?: { phase: "parse" | "resolution" | "runtime"; type: string }
+}
+
+const limits = { timeoutMs: 5000, maxToolCalls: undefined, maxOutputBytes: undefined }
+const prepared = ToolRuntime.prepare<never>({})
+
+export const run = async (file: string): Promise<Outcome> => {
+  const source = await Bun.file(path.join(root, file)).text()
+  const start = source.indexOf("/*---")
+  const meta = Bun.YAML.parse(source.slice(start + 5, source.indexOf("---*/", start))) as Frontmatter
+  let done: { error: unknown } | undefined
+  // Sloppy-only tests are never vendored, so every file runs as the strict half of test262's two-mode run.
+  // A host drains the job queue after an async test's script ends; the program end interrupts un-awaited
+  // work instead, so drain explicitly.
+  const drain = meta.flags?.includes("async") ? "\nfor (let i = 0; i < 100; i++) await null" : ""
+  const result = await Effect.runPromise(
+    executeProgram(`"use strict";\n${source}${drain}`, prepared, limits, {}, (host) =>
+      harness(host, (error) => {
+        done ??= { error }
+      }),
+    ),
+  )
+  if (meta.negative !== undefined) {
+    // Runtime negatives only check that execution failed: diagnostics do not carry the error name.
+    if (result.ok) return { status: "fail", reason: `expected ${meta.negative.type} but completed` }
+    if (meta.negative.phase === "runtime" || result.error.kind === "ParseError") return { status: "pass" }
+    return {
+      status: "fail",
+      reason: `expected ${meta.negative.type} but got ${result.error.kind}: ${result.error.message}`,
+    }
+  }
+  if (!result.ok) return { status: "fail", reason: `${result.error.kind}: ${result.error.message}` }
+  if (!meta.flags?.includes("async")) return { status: "pass" }
+  if (done === undefined) return { status: "fail", reason: "$DONE was never called" }
+  if (done.error !== undefined) return { status: "fail", reason: `$DONE: ${show(done.error)}` }
+  return { status: "pass" }
+}
+
+const harness = <R>(host: Host<R>, onDone: (error: unknown) => void): ReadonlyArray<readonly [string, unknown]> => {
+  const fail = (message: string) => Effect.fail(new ProgramThrow(createErrorValue("Test262Error", message)))
+  const prefix = (message: unknown) => (message === undefined ? "" : `${String(message)} `)
+  const compare = (a: unknown, b: unknown) =>
+    a instanceof ProgramArray &&
+    b instanceof ProgramArray &&
+    a.items.length === b.items.length &&
+    a.items.every((value, i) => Object.is(value, b.items[i]))
+  const test262Error = new HostFunction<R>({
+    name: "Test262Error",
+    call: (args) => Effect.succeed(createErrorValue("Test262Error", args[0] === undefined ? "" : String(args[0]))),
+    construct: (args) => Effect.succeed(createErrorValue("Test262Error", args[0] === undefined ? "" : String(args[0]))),
+    instanceOf: (value) => errorBrandName(value) === "Test262Error",
+    members: { thrower: new HostFunction<R>({ name: "Test262Error.thrower", call: (args) => fail(String(args[0])) }) },
+  })
+  const compareArray = new HostFunction<R>({
+    name: "compareArray",
+    call: (args) => Effect.succeed(compare(args[0], args[1])),
+    members: {
+      format: new HostFunction<R>({ name: "compareArray.format", call: (args) => Effect.succeed(show(args[0])) }),
+    },
+  })
+  const assert = new HostFunction<R>({
+    name: "assert",
+    call: (args) =>
+      args[0] === true
+        ? Effect.void
+        : fail(args[1] === undefined ? `Expected true but got ${show(args[0])}` : String(args[1])),
+    members: {
+      sameValue: new HostFunction<R>({
+        name: "assert.sameValue",
+        call: (args) =>
+          Object.is(args[0], args[1])
+            ? Effect.void
+            : fail(`${prefix(args[2])}Expected SameValue(«${show(args[0])}», «${show(args[1])}») to be true`),
+      }),
+      notSameValue: new HostFunction<R>({
+        name: "assert.notSameValue",
+        call: (args) =>
+          Object.is(args[0], args[1])
+            ? fail(`${prefix(args[2])}Expected SameValue(«${show(args[0])}», «${show(args[1])}») to be false`)
+            : Effect.void,
+      }),
+      compareArray: new HostFunction<R>({
+        name: "assert.compareArray",
+        call: (args) =>
+          compare(args[0], args[1])
+            ? Effect.void
+            : fail(
+                `Actual ${show(args[0])} and expected ${show(args[1])} should have the same contents. ${prefix(args[2])}`,
+              ),
+      }),
+      throws: new HostFunction<R>({
+        name: "assert.throws",
+        call: (args, node) => {
+          const expected = args[0] instanceof HostFunction ? args[0].name : show(args[0])
+          return host.runner.invokeCallable(args[1], [], node).pipe(
+            Effect.matchCauseEffect({
+              onFailure: (cause) => {
+                if (cause.reasons.some(Cause.isInterruptReason)) return Effect.failCause(cause)
+                const thrown = caughtErrorValue(Cause.squash(cause))
+                if (thrown === null || typeof thrown !== "object") {
+                  return fail(`${prefix(args[2])}Thrown value was not an object!`)
+                }
+                const actual = errorBrandName(thrown)
+                if (actual === expected) return Effect.void
+                return fail(`${prefix(args[2])}Expected a ${expected} but got a ${actual ?? "non-error object"}`)
+              },
+              onSuccess: () =>
+                fail(`${prefix(args[2])}Expected a ${expected} to be thrown but no exception was thrown at all`),
+            }),
+          )
+        },
+      }),
+    },
+  })
+  return [
+    ["assert", assert],
+    ["compareArray", compareArray],
+    ["Test262Error", test262Error],
+    ["$DONE", new HostFunction<R>({ name: "$DONE", call: (args) => Effect.sync(() => onDone(args[0])) })],
+    [
+      "$DONOTEVALUATE",
+      new HostFunction<R>({
+        name: "$DONOTEVALUATE",
+        call: () => Effect.fail(new ProgramThrow("Test262: This statement should not be evaluated.")),
+      }),
+    ],
+  ]
+}
+
+const show = (value: unknown): string => {
+  if (typeof value === "string") return JSON.stringify(value)
+  if (Object.is(value, -0)) return "-0"
+  if (value instanceof ProgramArray) return `[${value.items.map(show).join(", ")}]`
+  if (value instanceof HostFunction) return value.name
+  if (!(value instanceof ProgramObject)) return String(value)
+  const message = get(value, "message")
+  return typeof message === "string" ? `${errorBrandName(value) ?? "object"}: ${message}` : "object"
+}
@@ -0,0 +1,486 @@
+built-ins/Array/prototype/concat/create-ctor-non-object.js  # a.concat() throws a TypeError exception Expected a TypeError to be thrown but no exception was throw
+built-ins/Array/prototype/copyWithin/coerced-values-end.js  # Array.copyWithin expects end to be a number.
+built-ins/Array/prototype/copyWithin/coerced-values-start-change-target.js  # Array.copyWithin expects start to be a number.
+built-ins/Array/prototype/copyWithin/coerced-values-start.js  # Array.copyWithin expects start to be a number.
+built-ins/Array/prototype/copyWithin/coerced-values-target.js  # Array.copyWithin expects target index to be a number.
+built-ins/Array/prototype/copyWithin/fill-holes.js  # .hasOwnProperty is not a function.
+built-ins/Array/prototype/copyWithin/return-abrupt-from-end.js  # Expected a Test262Error but got a Error
+built-ins/Array/prototype/copyWithin/return-abrupt-from-start.js  # Expected a Test262Error but got a Error
+built-ins/Array/prototype/copyWithin/return-abrupt-from-target.js  # Expected a Test262Error but got a Error
+built-ins/Array/prototype/entries/iteration-mutable.js  # .next is not a function.
+built-ins/Array/prototype/entries/iteration.js  # .next is not a function.
+built-ins/Array/prototype/every/15.4.4.16-7-7.js  # .hasOwnProperty is not a function.
+built-ins/Array/prototype/every/15.4.4.16-8-13.js  # Property key must be a string or number, or Symbol.asyncIterator/Symbol.iterator.
+built-ins/Array/prototype/fill/coerced-indexes.js  # Array.fill expects start to be a number.
+built-ins/Array/prototype/fill/return-abrupt-from-end.js  # Expected a Test262Error but got a Error
+built-ins/Array/prototype/fill/return-abrupt-from-start.js  # Expected a Test262Error but got a Error
+built-ins/Array/prototype/filter/15.4.4.20-10-4.js  # Property key must be a string or number, or Symbol.asyncIterator/Symbol.iterator.
+built-ins/Array/prototype/filter/create-ctor-non-object.js  # null value Expected a TypeError to be thrown but no exception was thrown at all
+built-ins/Array/prototype/flat/non-numeric-depth-should-not-throw.js  # Array.flat expects depth to be a number.
+built-ins/Array/prototype/forEach/15.4.4.18-8-12.js  # Property key must be a string or number, or Symbol.asyncIterator/Symbol.iterator.
+built-ins/Array/prototype/includes/length-zero-returns-false.js  # Array.includes expects a value and optional start index.
+built-ins/Array/prototype/includes/no-arg.js  # Array.includes expects a value and optional start index.
+built-ins/Array/prototype/includes/return-abrupt-tointeger-fromindex.js  # Expected a Test262Error but got a Error
+built-ins/Array/prototype/includes/tointeger-fromindex.js  # Array.includes expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-1.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-15.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-16.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-17.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-18.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-19.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-20.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-21.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-22.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-23.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-24.js  # Expected a TypeError but got a Error
+built-ins/Array/prototype/indexOf/15.4.4.14-5-3.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-5-5.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-9-7.js  # Array assignment result contains a circular value.
+built-ins/Array/prototype/indexOf/15.4.4.14-9-8.js  # .toString is not a function.
+built-ins/Array/prototype/indexOf/15.4.4.14-9-a-3.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/15.4.4.14-9-a-6.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/indexOf/length-zero-returns-minus-one.js  # Array.indexOf expects start index to be a number.
+built-ins/Array/prototype/join/S15.4.4.5_A1.2_T2.js  # Array.join expects zero arguments or one string separator.
+built-ins/Array/prototype/join/S15.4.4.5_A3.1_T1.js  # Array.join expects zero arguments or one string separator.
+built-ins/Array/prototype/join/S15.4.4.5_A3.1_T2.js  # Array.join expects zero arguments or one string separator.
+built-ins/Array/prototype/join/S15.4.4.5_A3.2_T2.js  # x.join() must return "*" Expected SameValue(«"[object Object]"», «"*"») to be true
+built-ins/Array/prototype/keys/iteration-mutable.js  # .next is not a function.
+built-ins/Array/prototype/keys/iteration.js  # .next is not a function.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-1.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-15.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-16.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-17.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-18.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-19.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-20.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-21.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-22.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-23.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-24.js  # Expected a TypeError but got a Error
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-3.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-4.js  # a.lastIndexOf(2,undefined) Expected SameValue(«1», «-1») to be true
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-5.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-8-7.js  # Array assignment result contains a circular value.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-8-8.js  # .toString is not a function.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-8-a-3.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/15.4.4.15-8-a-6.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/lastIndexOf/length-zero-returns-minus-one.js  # Array.lastIndexOf expects start index to be a number.
+built-ins/Array/prototype/map/15.4.4.19-8-7.js  # .toString is not a function.
+built-ins/Array/prototype/map/15.4.4.19-9-4.js  # Property key must be a string or number, or Symbol.asyncIterator/Symbol.iterator.
+built-ins/Array/prototype/map/create-ctor-non-object.js  # null value Expected a TypeError to be thrown but no exception was thrown at all
+built-ins/Array/prototype/push/S15.4.4.7_A3.js  # The value of x[4294967295] is expected to be "x" Expected SameValue(«undefined», «"x"») to be true
+built-ins/Array/prototype/reduce/15.4.4.21-10-8.js  # Property key must be a string or number, or Symbol.asyncIterator/Symbol.iterator.
+built-ins/Array/prototype/reduce/15.4.4.21-9-7.js  # .hasOwnProperty is not a function.
+built-ins/Array/prototype/reduceRight/15.4.4.22-10-8.js  # Property key must be a string or number, or Symbol.asyncIterator/Symbol.iterator.
+built-ins/Array/prototype/reduceRight/15.4.4.22-9-7.js  # .hasOwnProperty is not a function.
+built-ins/Array/prototype/slice/create-ctor-non-object.js  # null value Expected a TypeError to be thrown but no exception was thrown at all
+built-ins/Array/prototype/some/15.4.4.17-8-13.js  # Property key must be a string or number, or Symbol.asyncIterator/Symbol.iterator.
+built-ins/Array/prototype/sort/S15.4.4.11_A2.1_T3.js  # #1: Check ToString operator
+built-ins/Array/prototype/sort/S15.4.4.11_A2.2_T3.js  # #1: Check ToString operator
+built-ins/Array/prototype/sort/bug_596_1.js  # #1: [object, object].sort(); counter < 2. Actual: 0
+built-ins/Array/prototype/sort/bug_596_2.js  # .hasOwnProperty is not a function.
+built-ins/Array/prototype/splice/create-ctor-non-object.js  # null value Expected a TypeError to be thrown but no exception was thrown at all
+built-ins/Array/prototype/toLocaleString/S15.4.4.3_A1_T1.js  # .toLocaleString is not a function.
+built-ins/Array/prototype/toString/S15.4.4.2_A1_T1.js  # .toString is not a function.
+built-ins/Array/prototype/toString/S15.4.4.2_A1_T2.js  # .toString is not a function.
+built-ins/Array/prototype/toString/S15.4.4.2_A1_T3.js  # .toString is not a function.
+built-ins/Array/prototype/toString/S15.4.4.2_A1_T4.js  # .toString is not a function.
+built-ins/Array/prototype/values/iteration-mutable.js  # .next is not a function.
+built-ins/Array/prototype/values/iteration.js  # .next is not a function.
+language/statements/async-function/rest-params-trailing-comma-early-error.js  # expected SyntaxError but the program ran
+language/statements/async-generator/dflt-params-abrupt.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dflt-params-ref-later.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/async-generator/dflt-params-ref-self.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-init-iter-get-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-ptrn-elem-ary-val-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-ptrn-elem-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-ptrn-elem-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-ptrn-elem-id-iter-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-ptrn-elem-obj-val-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-ptrn-elision-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-ptrn-rest-id-elision-next-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/ary-ptrn-rest-id-iter-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-init-iter-get-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-ptrn-elem-ary-val-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-ptrn-elem-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-ptrn-elem-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-ptrn-elem-id-iter-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-ptrn-elem-obj-val-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-ptrn-elision-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-ptrn-rest-id-elision-next-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-ary-ptrn-rest-id-iter-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-init-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-init-undefined.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-ptrn-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-ptrn-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-ptrn-list-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-ptrn-prop-ary-value-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-ptrn-prop-eval-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-ptrn-prop-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-ptrn-prop-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-ptrn-prop-obj-value-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/dflt-obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-init-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-init-undefined.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-ptrn-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-ptrn-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-ptrn-list-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-ptrn-prop-ary-value-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-ptrn-prop-eval-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-ptrn-prop-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-ptrn-prop-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-ptrn-prop-obj-value-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/dstr/obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/async-generator/rest-params-trailing-comma-early-error.js  # expected SyntaxError but the program ran
+language/statements/async-generator/return-undefined-implicit-and-explicit.js  # Actual ["tick 1", "tick 2", "g1 ret", "g2 ret", "g3 ret", "g4 ret"] and expected ["tick 1", "g1 ret"
+language/statements/const/dstr/ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/const/dstr/ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/const/dstr/obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/const/dstr/obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/const/dstr/obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/const/dstr/obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/for-await-of/async-func-decl-dstr-array-elem-init-in.js  # Failed to parse TypeScript: '…' expected.
+language/statements/for-await-of/async-func-decl-dstr-array-elem-nested-array-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-nested-array-undefined-hole.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-nested-array-undefined-own.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-nested-array-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-nested-obj-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-nested-obj-undefined-hole.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-nested-obj-undefined-own.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-nested-obj-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-put-const.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-put-unresolvable-strict.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-decl-dstr-array-elem-trlg-iter-elision-iter-nrml-close-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-decl-dstr-obj-empty-bool.js  # Object destructuring requires a data object or array value, received a boolean.
+language/statements/for-await-of/async-func-decl-dstr-obj-empty-num.js  # Object destructuring requires a data object or array value, received a number.
+language/statements/for-await-of/async-func-decl-dstr-obj-empty-string.js  # Object destructuring requires a data object or array value, received a string.
+language/statements/for-await-of/async-func-decl-dstr-obj-rest-number.js  # Object destructuring requires a data object or array value, received a number.
+language/statements/for-await-of/async-func-decl-dstr-obj-rest-str-val.js  # Object destructuring requires a data object or array value, received a string.
+language/statements/for-await-of/async-func-dstr-const-ary-init-iter-get-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-ary-ptrn-elem-ary-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-const-ary-ptrn-elem-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-ary-ptrn-elem-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-dstr-const-ary-ptrn-elem-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-ary-ptrn-elem-obj-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-const-ary-ptrn-elem-obj-val-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-const-ary-ptrn-elision-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-ary-ptrn-rest-id-elision-next-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-ary-ptrn-rest-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-init-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-init-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-ptrn-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-ptrn-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-ptrn-list-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-ptrn-prop-ary-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-ptrn-prop-eval-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-ptrn-prop-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-ptrn-prop-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-ptrn-prop-obj-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-const-obj-ptrn-prop-obj-value-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-init-iter-get-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-ptrn-elem-ary-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-ptrn-elem-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-ptrn-elem-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-ptrn-elem-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-ptrn-elem-obj-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-ptrn-elem-obj-val-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-ptrn-elision-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-ptrn-rest-id-elision-next-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-ary-ptrn-rest-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-init-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-init-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-ptrn-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-ptrn-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-ptrn-list-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-ptrn-prop-ary-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-ptrn-prop-eval-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-ptrn-prop-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-ptrn-prop-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-ptrn-prop-obj-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-let-obj-ptrn-prop-obj-value-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-init-iter-get-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-ptrn-elem-ary-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-ptrn-elem-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-ptrn-elem-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-ptrn-elem-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-ptrn-elem-obj-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-ptrn-elem-obj-val-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-ptrn-elision-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-ptrn-rest-id-elision-next-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-ary-ptrn-rest-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-init-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-init-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-ptrn-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-ptrn-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-ptrn-list-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-ptrn-prop-ary-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-ptrn-prop-eval-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-ptrn-prop-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-ptrn-prop-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-ptrn-prop-obj-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-func-dstr-var-obj-ptrn-prop-obj-value-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-init-in.js  # Failed to parse TypeScript: '…' expected.
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-iter-get-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-iter-nrml-close-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-iter-nrml-close-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-iter-rtrn-close-null.js  # "Promise incorrectly fulfilled."
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-nested-array-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-nested-array-undefined-hole.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-nested-array-undefined-own.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-nested-array-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-nested-obj-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-nested-obj-undefined-hole.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-nested-obj-undefined-own.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-nested-obj-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-put-const.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-put-unresolvable-strict.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-trlg-iter-elision-iter-nrml-close-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-trlg-iter-elision-iter-nrml-close-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-trlg-iter-list-nrml-close-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-decl-dstr-array-elem-trlg-iter-list-thrw-close-skip.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-decl-dstr-obj-empty-bool.js  # Object destructuring requires a data object or array value, received a boolean.
+language/statements/for-await-of/async-gen-decl-dstr-obj-empty-num.js  # Object destructuring requires a data object or array value, received a number.
+language/statements/for-await-of/async-gen-decl-dstr-obj-empty-string.js  # Object destructuring requires a data object or array value, received a string.
+language/statements/for-await-of/async-gen-decl-dstr-obj-rest-number.js  # Object destructuring requires a data object or array value, received a number.
+language/statements/for-await-of/async-gen-decl-dstr-obj-rest-str-val.js  # Object destructuring requires a data object or array value, received a string.
+language/statements/for-await-of/async-gen-dstr-const-ary-init-iter-get-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-ary-ptrn-elem-ary-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-const-ary-ptrn-elem-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-ary-ptrn-elem-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-dstr-const-ary-ptrn-elem-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-ary-ptrn-elem-obj-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-const-ary-ptrn-elem-obj-val-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-const-ary-ptrn-elision-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-ary-ptrn-rest-id-elision-next-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-ary-ptrn-rest-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-init-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-init-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-ptrn-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-ptrn-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-ptrn-list-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-ptrn-prop-ary-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-ptrn-prop-eval-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-ptrn-prop-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-ptrn-prop-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-ptrn-prop-obj-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-const-obj-ptrn-prop-obj-value-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-init-iter-get-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-ptrn-elem-ary-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-ptrn-elem-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-ptrn-elem-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-ptrn-elem-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-ptrn-elem-obj-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-ptrn-elem-obj-val-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-ptrn-elision-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-ptrn-rest-id-elision-next-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-ary-ptrn-rest-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-init-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-init-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-ptrn-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-ptrn-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-ptrn-list-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-ptrn-prop-ary-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-ptrn-prop-eval-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-ptrn-prop-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-ptrn-prop-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-ptrn-prop-obj-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-let-obj-ptrn-prop-obj-value-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-init-iter-get-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-ptrn-elem-ary-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-ptrn-elem-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-ptrn-elem-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-ptrn-elem-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-ptrn-elem-obj-val-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-ptrn-elem-obj-val-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-ptrn-elision-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-ptrn-rest-id-elision-next-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-ary-ptrn-rest-id-iter-step-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-init-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-init-undefined.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-list-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-prop-ary-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-prop-eval-err.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-prop-id-init-throws.js  # Expected SameValue(«undefined», «Test262Error») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-prop-id-init-unresolvable.js  # Expected SameValue(«undefined», «ReferenceError») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-prop-obj-value-null.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-await-of/async-gen-dstr-var-obj-ptrn-prop-obj-value-undef.js  # Expected SameValue(«undefined», «TypeError») to be true
+language/statements/for-in/12.6.4-1.js  # .hasOwnProperty is not a function.
+language/statements/for-in/head-lhs-member.js  # Unsupported for...in binding.
+language/statements/for-of/Array.prototype.Symbol.iterator.js  # The called value is not a function.
+language/statements/for-of/dstr/array-elem-init-in.js  # Failed to parse TypeScript: '…' expected.
+language/statements/for-of/dstr/array-elem-iter-rtrn-close-err.js  # Iterator next must be a function.
+language/statements/for-of/dstr/array-elem-iter-rtrn-close-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/for-of/dstr/array-elem-iter-thrw-close-err.js  # Expected SameValue(«1», «0») to be true
+language/statements/for-of/dstr/array-elem-nested-obj-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/array-elem-nested-obj-undefined-hole.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/array-elem-nested-obj-undefined-own.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/array-elem-nested-obj-undefined.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/array-elem-trlg-iter-list-rtrn-close-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/for-of/dstr/array-elem-trlg-iter-list-rtrn-close-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/for-of/dstr/array-elem-trlg-iter-list-thrw-close-err.js  # Expected SameValue(«1», «0») to be true
+language/statements/for-of/dstr/array-elem-trlg-iter-rest-rtrn-close-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/for-of/dstr/array-elem-trlg-iter-rest-rtrn-close-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/for-of/dstr/array-elem-trlg-iter-rest-thrw-close-err.js  # Expected SameValue(«11», «1») to be true
+language/statements/for-of/dstr/array-rest-iter-rtrn-close-err.js  # Iterator next must be a function.
+language/statements/for-of/dstr/array-rest-iter-rtrn-close-null.js  # Iterator next must be a function.
+language/statements/for-of/dstr/array-rest-iter-thrw-close-err.js  # Expected SameValue(«11», «0») to be true
+language/statements/for-of/dstr/array-rest-lref-err.js  # Expected SameValue(«1», «0») to be true
+language/statements/for-of/dstr/const-ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/const-ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/const-obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/const-obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/const-obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/const-obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/let-ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/let-ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/let-obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/let-obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/let-obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/let-obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/obj-empty-bool.js  # Object destructuring requires a data object or array value, received a boolean.
+language/statements/for-of/dstr/obj-empty-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/obj-empty-num.js  # Object destructuring requires a data object or array value, received a number.
+language/statements/for-of/dstr/obj-empty-string.js  # Object destructuring requires a data object or array value, received a string.
+language/statements/for-of/dstr/obj-empty-undef.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/obj-prop-name-evaluation-error.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/obj-prop-nested-obj-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/obj-prop-nested-obj-undefined-own.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/obj-prop-nested-obj-undefined.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/obj-rest-number.js  # Object destructuring requires a data object or array value, received a number.
+language/statements/for-of/dstr/obj-rest-str-val.js  # Object destructuring requires a data object or array value, received a string.
+language/statements/for-of/dstr/obj-rest-val-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/obj-rest-val-undefined.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/var-ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/var-ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/var-obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/var-obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/var-obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/for-of/dstr/var-obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/for-of/throw-from-catch.js  # … cannot be constructed: user-defined constructors and classes are not supported. Call it as a funct
+language/statements/for-of/throw-from-finally.js  # … cannot be constructed: user-defined constructors and classes are not supported. Call it as a funct
+language/statements/for-of/throw.js  # … cannot be constructed: user-defined constructors and classes are not supported. Call it as a funct
+language/statements/for/dstr/const-ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/const-ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/const-obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/const-obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/const-obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/const-obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/let-ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/let-ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/let-obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/let-obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/let-obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/let-obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/var-ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/var-ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/var-obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/var-obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/var-obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/for/dstr/var-obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/function/13.2-19-b-3gs.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/function/13.2-2-s.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/function/S13.2.1_A5_T1.js  # .toString is not a function.
+language/statements/function/S13.2_A7_T1.js  # The called value is not a function.
+language/statements/function/S13_A3_T1.js  # Unknown identifier '…'.
+language/statements/function/S13_A6_T1.js  # Identifier '…' has already been declared.
+language/statements/function/S14_A2.js  # Unknown identifier '…'.
+language/statements/function/S14_A5_T1.js  # Identifier '…' has already been declared.
+language/statements/function/S14_A5_T2.js  # Identifier '…' has already been declared.
+language/statements/function/dstr/ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/dflt-ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/dflt-ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/dflt-obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/dflt-obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/dflt-obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/dflt-obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/function/dstr/obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/function/rest-params-trailing-comma-early-error.js  # expected SyntaxError but the program ran
+language/statements/generators/dflt-params-abrupt.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dflt-params-ref-later.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/generators/dflt-params-ref-self.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-init-iter-get-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-ptrn-elem-ary-val-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-ptrn-elem-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-ptrn-elem-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-ptrn-elem-id-iter-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-ptrn-elem-obj-val-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-ptrn-elision-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-ptrn-rest-id-elision-next-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/ary-ptrn-rest-id-iter-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-init-iter-get-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-ptrn-elem-ary-val-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-ptrn-elem-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-ptrn-elem-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-ptrn-elem-id-iter-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-ptrn-elem-obj-val-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-ptrn-elision-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-ptrn-rest-id-elision-next-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-ary-ptrn-rest-id-iter-step-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-init-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-init-undefined.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-ptrn-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-ptrn-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-ptrn-list-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-ptrn-prop-ary-value-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-ptrn-prop-eval-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-ptrn-prop-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-ptrn-prop-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-ptrn-prop-obj-value-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/dflt-obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-init-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-init-undefined.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-ptrn-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-ptrn-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-ptrn-list-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-ptrn-prop-ary-value-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-ptrn-prop-eval-err.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-ptrn-prop-id-init-throws.js  # Expected a Test262Error to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-ptrn-prop-id-init-unresolvable.js  # Expected a ReferenceError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-ptrn-prop-obj-value-null.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/dstr/obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError to be thrown but no exception was thrown at all
+language/statements/generators/has-instance.js  # The right-hand side of '…' must be a supported constructor: Error (or a specific error type like Typ
+language/statements/generators/rest-params-trailing-comma-early-error.js  # expected SyntaxError but the program ran
+language/statements/labeled/value-await-non-module-escaped.js  # Failed to parse TypeScript: Keywords cannot contain escape characters.
+language/statements/labeled/value-await-non-module.js  # Failed to parse TypeScript: Expression expected.
+language/statements/let/dstr/ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/let/dstr/ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/let/dstr/obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/let/dstr/obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/let/dstr/obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/let/dstr/obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/return/S12.9_A1_T1.js  # expected SyntaxError but the program ran
+language/statements/return/S12.9_A1_T10.js  # expected SyntaxError but the program ran
+language/statements/return/S12.9_A1_T2.js  # expected SyntaxError but the program ran
+language/statements/return/S12.9_A1_T3.js  # expected SyntaxError but the program ran
+language/statements/return/S12.9_A1_T4.js  # expected SyntaxError but the program ran
+language/statements/return/S12.9_A1_T5.js  # expected SyntaxError but the program ran
+language/statements/return/S12.9_A1_T6.js  # expected SyntaxError but the program ran
+language/statements/return/S12.9_A1_T7.js  # expected SyntaxError but the program ran
+language/statements/return/S12.9_A1_T8.js  # expected SyntaxError but the program ran
+language/statements/return/S12.9_A1_T9.js  # expected SyntaxError but the program ran
+language/statements/switch/S12.11_A1_T4.js  # Switch discriminants must be data values.
+language/statements/switch/scope-lex-open-dflt.js  # Switch discriminants must be data values.
+language/statements/try/S12.14_A19_T1.js  # .toString is not a function.
+language/statements/try/S12.14_A19_T2.js  # .toString is not a function.
+language/statements/try/dstr/ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/try/dstr/ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/try/dstr/obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/try/dstr/obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/try/dstr/obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/try/dstr/obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
+language/statements/variable/dstr/ary-ptrn-elem-obj-val-null.js  # Expected a TypeError but got a Error
+language/statements/variable/dstr/ary-ptrn-elem-obj-val-undef.js  # Expected a TypeError but got a Error
+language/statements/variable/dstr/obj-init-null.js  # Expected a TypeError but got a Error
+language/statements/variable/dstr/obj-init-undefined.js  # Expected a TypeError but got a Error
+language/statements/variable/dstr/obj-ptrn-prop-obj-value-null.js  # Expected a TypeError but got a Error
+language/statements/variable/dstr/obj-ptrn-prop-obj-value-undef.js  # Expected a TypeError but got a Error
@@ -192,9 +192,10 @@ describe("blocked member names on tool paths", () => {
      `,
      ),
    ).toEqual([true, true, true, null, true, null, null, null, true, null, null, "undefined"])
-    expect((await failure(runtime, `return (() => 1).constructor`)).message).toContain(
-      "Cannot read properties of a function",
-    )
+    expect(await value(runtime, `return [(() => 1).constructor, typeof (() => 1).__proto__]`)).toEqual([
+      null,
+      "undefined",
+    ])
    const escape = await failure(runtime, `return ({}).constructor.constructor.constructor("return 1")()`)
    expect(escape.message).toContain("Cannot access a property on a non-object value")
    const poisoned = await failure(runtime, `const o = {}; o.__proto__.constructor("return 1")`)
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Dax Raad	0f26ad8787	fix(cli): keep opencode2 as a working alias	2026-09-11 20:55:03 -04:00
Dax Raad	b08ad82518	fix(cli): clarify opencode2 rename guidance	2026-09-11 20:50:20 -04:00
Dax	5319f063d6	docs: use stable V2 packages (#48576 )	2026-09-11 20:33:18 -04:00
Dax	63f7ceecbe	fix(release): use V2 Docker artifact paths (#48571 )	2026-09-11 19:46:37 -04:00
Dax	770420bdad	fix(release): omit node CLI from latest (#48568 )	2026-09-11 19:10:23 -04:00
Dax	4994a7d694	fix(release): sign primary Windows CLI (#48567 )	2026-09-11 19:08:34 -04:00
Dax	c55ee2a815	fix(release): sign v2 Windows CLI (#48566 )	2026-09-11 18:55:07 -04:00
Dax	312651f68e	feat(tui): configure session permission handling (#48545 )	2026-09-11 19:50:39 +00:00
Dax	654f411a5b	feat(release): isolate v2 stable publishing (#48546 )	2026-09-11 15:50:35 -04:00
Aiden Cline	68b862da49	refactor(codemode): make functions program objects with name and length (#48541 )	2026-09-11 14:50:07 -05:00
Dax	8f2b13e864	fix(tui): display slash command aliases (#48544 )	2026-09-11 15:34:33 -04:00
Dax	bb564f96a3	feat(cli): rename command to opencode	2026-09-11 15:03:45 -04:00
Aiden Cline	a555f24ded	refactor: flatten provider settings across core and the AI package (#48429 )	2026-09-11 13:37:24 -05:00
Aiden Cline	10ae321bf3	refactor(codemode): give programs their own objects and arrays (#48527 )	2026-09-11 13:36:35 -05:00
Aiden Cline	6e8ff0c2b7	refactor(core): remove dead AISDK hooks (#48523 )	2026-09-11 12:41:20 -05:00
Aiden Cline	923bda07a2	feat(ai): always send interleaved thinking beta for Anthropic (#48521 )	2026-09-11 12:29:18 -05:00
Aiden Cline	4c34ee5eab	test(codemode): run test262 files verbatim from a local checkout (#48446 )	2026-09-11 10:40:02 -05:00