diff --git a/.github/workflows/rusty-v8-release.yml b/.github/workflows/rusty-v8-release.yml
index 92be3761dd..bddb5aba53 100644
--- a/.github/workflows/rusty-v8-release.yml
+++ b/.github/workflows/rusty-v8-release.yml
@@ -99,6 +99,7 @@ jobs:
             target: aarch64-unknown-linux-gnu
             v8_cpu: arm64
             variant: ptrcomp-sandbox
+          # Keep the build on arm64; smoke-macos-x86 tests its staged output on Intel.
           - runner: macos-15-xlarge
             bazel_config: ci-macos
             platform: macos_amd64
@@ -285,6 +286,68 @@ jobs:
           name: rusty-v8-${{ needs.metadata.outputs.v8_version }}-${{ matrix.variant }}-${{ matrix.target }}
           path: dist/${{ matrix.target }}/*
 
+  smoke-macos-x86:
+    name: Smoke test ${{ matrix.variant }} x86_64-apple-darwin on Intel
+    needs:
+      - metadata
+      - build
+    runs-on: macos-15-large
+    permissions:
+      actions: read
+      contents: read
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - sandbox: false
+            variant: release
+          - sandbox: true
+            variant: ptrcomp-sandbox
+
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
+      - name: Set up Rust toolchain
+        uses: dtolnay/rust-toolchain@e081816240890017053eacbb1bdf337761dc5582 # 1.95.0
+        with:
+          toolchain: "1.95.0"
+
+      - name: Download staged artifact
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
+        with:
+          name: rusty-v8-${{ needs.metadata.outputs.v8_version }}-${{ matrix.variant }}-x86_64-apple-darwin
+          path: dist/x86_64-apple-darwin
+
+      - name: Smoke test staged artifact with Cargo
+        env:
+          SANDBOX: ${{ matrix.sandbox }}
+          TARGET: x86_64-apple-darwin
+        shell: bash
+        run: |
+          set -euo pipefail
+
+          archive="$(find "dist/${TARGET}" -maxdepth 1 -type f -name 'librusty_v8_*.a.gz' -print -quit)"
+          binding="$(find "dist/${TARGET}" -maxdepth 1 -type f -name 'src_binding_*.rs' -print -quit)"
+          if [[ -z "${archive}" || -z "${binding}" ]]; then
+            echo "Missing staged archive or binding for ${TARGET}." >&2
+            exit 1
+          fi
+
+          cargo_args=(test -p codex-v8-poc)
+          if [[ "${SANDBOX}" == "true" ]]; then
+            cargo_args+=(--features sandbox)
+          fi
+
+          (
+            cd codex-rs
+            CARGO_TARGET_DIR="${RUNNER_TEMP}/rusty-v8-cargo-smoke-${TARGET}-${SANDBOX}" \
+            RUSTY_V8_ARCHIVE="${GITHUB_WORKSPACE}/${archive}" \
+            RUSTY_V8_SRC_BINDING_PATH="${GITHUB_WORKSPACE}/${binding}" \
+            cargo "${cargo_args[@]}"
+          )
+
   build-windows-source:
     name: Build ptrcomp-sandbox ${{ matrix.target }} from source
     needs: metadata
@@ -429,6 +492,7 @@ jobs:
       - metadata
       - build
       - build-windows-source
+      - smoke-macos-x86
     runs-on: ubuntu-latest
     permissions:
       contents: write
diff --git a/.github/workflows/v8-canary.yml b/.github/workflows/v8-canary.yml
index 53d9585108..46c0e5065a 100644
--- a/.github/workflows/v8-canary.yml
+++ b/.github/workflows/v8-canary.yml
@@ -119,6 +119,7 @@ jobs:
             target: aarch64-unknown-linux-gnu
             v8_cpu: arm64
             variant: ptrcomp-sandbox
+          # Keep the build on arm64; smoke-macos-x86 tests its staged output on Intel.
           - runner: macos-15-xlarge
             bazel_config: ci-macos
             platform: macos_amd64
@@ -306,6 +307,74 @@ jobs:
         if: always() && !cancelled()
         uses: ./.github/actions/check-clean-worktree
 
+  smoke-macos-x86:
+    name: Smoke test ${{ matrix.variant }} x86_64-apple-darwin on Intel
+    needs:
+      - metadata
+      - build
+    if: ${{ needs.metadata.outputs.canary_required == 'true' }}
+    runs-on: macos-15-large
+    permissions:
+      actions: read
+      contents: read
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - sandbox: false
+            variant: release
+          - sandbox: true
+            variant: ptrcomp-sandbox
+
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          ref: ${{ github.event_name == 'pull_request' && github.event.pull_request.head.sha || github.sha }}
+          persist-credentials: false
+
+      - name: Set up Rust toolchain
+        uses: dtolnay/rust-toolchain@e081816240890017053eacbb1bdf337761dc5582 # 1.95.0
+        with:
+          toolchain: "1.95.0"
+
+      - name: Download staged artifact
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
+        with:
+          name: v8-canary-${{ needs.metadata.outputs.v8_version }}-${{ matrix.variant }}-x86_64-apple-darwin
+          path: dist/x86_64-apple-darwin
+
+      - name: Smoke test staged artifact with Cargo
+        env:
+          SANDBOX: ${{ matrix.sandbox }}
+          TARGET: x86_64-apple-darwin
+        shell: bash
+        run: |
+          set -euo pipefail
+
+          archive="$(find "dist/${TARGET}" -maxdepth 1 -type f -name 'librusty_v8_*.a.gz' -print -quit)"
+          binding="$(find "dist/${TARGET}" -maxdepth 1 -type f -name 'src_binding_*.rs' -print -quit)"
+          if [[ -z "${archive}" || -z "${binding}" ]]; then
+            echo "Missing staged archive or binding for ${TARGET}." >&2
+            exit 1
+          fi
+
+          cargo_args=(test -p codex-v8-poc)
+          if [[ "${SANDBOX}" == "true" ]]; then
+            cargo_args+=(--features sandbox)
+          fi
+
+          (
+            cd codex-rs
+            CARGO_TARGET_DIR="${RUNNER_TEMP}/rusty-v8-cargo-smoke-${TARGET}-${SANDBOX}" \
+            RUSTY_V8_ARCHIVE="${GITHUB_WORKSPACE}/${archive}" \
+            RUSTY_V8_SRC_BINDING_PATH="${GITHUB_WORKSPACE}/${binding}" \
+            cargo "${cargo_args[@]}"
+          )
+
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   build-windows-source:
     name: Build ptrcomp-sandbox ${{ matrix.target }} from source
     needs: metadata