feat: add production-ready Cog playground

.github/dependabot.yml

@@ -10,6 +10,10 @@ updates:
       interval: "weekly"
     allow:
       - dependency-type: "direct"
+  - package-ecosystem: "npm"
+    directory: "/playground"
+    schedule:
+      interval: "weekly"
   - package-ecosystem: "cargo"
     directory: "/crates"
     schedule:

.github/workflows/ci.yaml

@@ -63,6 +63,101 @@ jobs:
     steps:
       - run: echo "supported_pythons=$SUPPORTED_PYTHONS"
 
+  playground-changes:
+    name: Detect playground changes
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    outputs:
+      changed: ${{ steps.changes.outputs.changed }}
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+      - name: Check playground sources
+        id: changes
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha || github.event.merge_group.base_sha || github.event.before }}
+        run: |
+          if [[ "${{ github.event_name }}" == "workflow_dispatch" || -z "$BASE_SHA" || "$BASE_SHA" =~ ^0+$ ]]; then
+            echo "changed=true" >> "$GITHUB_OUTPUT"
+          elif git diff --quiet "$BASE_SHA" "$GITHUB_SHA" -- \
+            playground \
+            'pkg/cli/playground*' \
+            pkg/cli/root.go \
+            cmd/cog \
+            .goreleaser.yaml \
+            mise.toml \
+            mise.lock \
+            go.mod \
+            go.sum \
+            .github/workflows/ci.yaml \
+            .github/workflows/release-build.yaml; then
+            echo "changed=false" >> "$GITHUB_OUTPUT"
+          else
+            echo "changed=true" >> "$GITHUB_OUTPUT"
+          fi
+
+  fmt-playground:
+    name: Format playground
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/checkout@v6
+      - uses: jdx/mise-action@v4
+        with:
+          version: 2026.4.27
+          cache_key_prefix: mise-ci-${{ github.job }}
+      - name: Check formatting
+        run: mise run fmt:playground
+
+  lint-playground:
+    name: Lint playground
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/checkout@v6
+      - uses: jdx/mise-action@v4
+        with:
+          version: 2026.4.27
+          cache_key_prefix: mise-ci-${{ github.job }}
+      - name: Lint
+        run: mise run lint:playground
+
+  test-playground:
+    name: Test playground
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/checkout@v6
+      - uses: jdx/mise-action@v4
+        with:
+          version: 2026.4.27
+          cache_key_prefix: mise-ci-${{ github.job }}
+      - name: Test
+        run: mise run test:playground
+
+  playground-check:
+    name: Check playground
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/checkout@v6
+      - uses: jdx/mise-action@v4
+        with:
+          version: 2026.4.27
+          cache_key_prefix: mise-ci-${{ github.job }}
+      - name: Type check
+        run: mise run typecheck:playground
+      - name: Build embedded assets
+        run: mise run --force build:playground
+      - name: Test embedded assets
+        run: go test -tags playground_assets ./pkg/cli -run '^TestPlaygroundServesUI$'
+      - name: Upload playground assets
+        uses: actions/upload-artifact@v6
+        with:
+          name: PlaygroundAssets
+          path: pkg/cli/playground
+
 # =============================================================================
 # Version Check - Validates VERSION.txt format and sync
 # =============================================================================
@@ -183,6 +278,7 @@ jobs:
 
   build-cog:
     name: Build cog CLI
+    needs: [playground-changes, playground-check]
     runs-on: ubuntu-latest
     timeout-minutes: 15
     steps:
@@ -193,6 +289,11 @@ jobs:
         with:
           version: 2026.4.27
           cache_key_prefix: mise-ci-${{ github.job }}
+      - name: Download verified playground assets
+        uses: actions/download-artifact@v8
+        with:
+          name: PlaygroundAssets
+          path: pkg/cli/playground
       - name: Get version from VERSION.txt
         id: version
         run: echo "version=$(tr -d '[:space:]' < VERSION.txt)" >> "$GITHUB_OUTPUT"
@@ -532,6 +633,65 @@ jobs:
       - name: Test coglet-python bindings
         run: uvx nox -s coglet -p ${{ matrix.python-version }}
 
+  test-playground-e2e:
+    name: Playground Playwright integration tests (Chromium)
+    needs:
+      - playground-changes
+      - fmt-playground
+      - lint-playground
+      - test-playground
+      - playground-check
+      - build-cog
+      - build-sdk
+      - build-rust
+    if: needs.playground-changes.outputs.changed == 'true'
+    runs-on: ubuntu-latest-16-cores
+    timeout-minutes: 30
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+      - name: Login to Docker Hub
+        uses: docker/login-action@v4
+        if: github.event.pull_request.head.repo.full_name == github.repository || github.event_name != 'pull_request'
+        with:
+          registry: index.docker.io
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      - name: Download artifacts
+        uses: actions/download-artifact@v8
+        with:
+          path: dist
+          merge-multiple: true
+      - name: Install cog binary
+        run: |
+          cp dist/cog ./cog
+          chmod +x ./cog
+      - uses: jdx/mise-action@v4
+        with:
+          version: 2026.4.27
+          cache_key_prefix: mise-ci-${{ github.job }}
+      - name: Install playground dependencies and Chromium
+        run: |
+          mise run playground:install
+          pnpm --dir playground exec playwright install --with-deps chromium
+      - name: Run browser integration tests
+        env:
+          BUILDKIT_PROGRESS: quiet
+          COG_BINARY: ${{ github.workspace }}/cog
+          COG_REGISTRY_HOST: ghcr.io/replicate/cog
+          COG_SDK_WHEEL: ${{ github.workspace }}/dist
+          COGLET_WHEEL: ${{ github.workspace }}/dist
+        run: pnpm --dir playground run test:e2e
+      - name: Upload browser test report
+        if: failure()
+        uses: actions/upload-artifact@v6
+        with:
+          name: PlaygroundPlaywrightReport
+          path: |
+            playground/playwright-report
+            playground/test-results
+
   # Compute integration test shards dynamically.
   # Slow tests (tagged with [short] skip) are distributed round-robin first,
   # then remaining tests fill in. This ensures slow tests don't pile up on one runner.
@@ -696,6 +856,11 @@ jobs:
     name: CI Complete
     needs:
       - setup
+      - playground-changes
+      - fmt-playground
+      - lint-playground
+      - test-playground
+      - playground-check
       - version-check
       - build-cog
       - build-sdk
@@ -716,6 +881,7 @@ jobs:
       - test-rust
       - test-python
       - test-coglet-python
+      - test-playground-e2e
       - integration-shards
       - test-integration
     if: always()
@@ -725,6 +891,11 @@ jobs:
       - name: Check job results
         run: |
           echo "Job results:"
+          echo "  playground-changes: ${{ needs.playground-changes.result }}"
+          echo "  fmt-playground: ${{ needs.fmt-playground.result }}"
+          echo "  lint-playground: ${{ needs.lint-playground.result }}"
+          echo "  test-playground: ${{ needs.test-playground.result }}"
+          echo "  playground-check: ${{ needs.playground-check.result }}"
           echo "  version-check: ${{ needs.version-check.result }}"
           echo "  build-cog: ${{ needs.build-cog.result }}"
           echo "  build-sdk: ${{ needs.build-sdk.result }}"
@@ -745,41 +916,55 @@ jobs:
           echo "  test-rust: ${{ needs.test-rust.result }}"
           echo "  test-python: ${{ needs.test-python.result }}"
           echo "  test-coglet-python: ${{ needs.test-coglet-python.result }}"
+          echo "  test-playground-e2e: ${{ needs.test-playground-e2e.result }}"
           echo "  integration-shards: ${{ needs.integration-shards.result }}"
           echo "  test-integration: ${{ needs.test-integration.result }}"
 
-          # Fail if any required job failed.
-          # lint-rust-advisories is excluded: it uses continue-on-error because
-          # advisory DB updates shouldn't block unrelated PRs.
           FAILED=false
-          for result in \
-            "${{ needs.setup.result }}" \
-            "${{ needs.version-check.result }}" \
-            "${{ needs.build-cog.result }}" \
-            "${{ needs.build-sdk.result }}" \
-            "${{ needs.build-rust.result }}" \
-            "${{ needs.fmt-go.result }}" \
-            "${{ needs.fmt-rust.result }}" \
-            "${{ needs.fmt-python.result }}" \
-            "${{ needs.check-llm-docs.result }}" \
-            "${{ needs.check-stubs.result }}" \
-            "${{ needs.lint-go.result }}" \
-            "${{ needs.lint-rust.result }}" \
-            "${{ needs.lint-rust-deny.result }}" \
-            "${{ needs.lint-python.result }}" \
-            "${{ needs.lint-docs.result }}" \
-            "${{ needs.test-go.result }}" \
-            "${{ needs.fuzz-go.result }}" \
-            "${{ needs.test-rust.result }}" \
-            "${{ needs.test-python.result }}" \
-            "${{ needs.test-coglet-python.result }}" \
-            "${{ needs.integration-shards.result }}" \
-            "${{ needs.test-integration.result }}"
-          do
-            if [ "$result" = "failure" ] || [ "$result" = "cancelled" ]; then
+          check_success() {
+            if [ "$2" != "success" ]; then
+              echo "::error::$1 finished with unexpected result: $2"
               FAILED=true
             fi
-          done
+          }
+
+          # lint-rust-advisories is informational and intentionally excluded.
+          check_success setup "${{ needs.setup.result }}"
+          check_success playground-changes "${{ needs.playground-changes.result }}"
+          check_success fmt-playground "${{ needs.fmt-playground.result }}"
+          check_success lint-playground "${{ needs.lint-playground.result }}"
+          check_success test-playground "${{ needs.test-playground.result }}"
+          check_success playground-check "${{ needs.playground-check.result }}"
+          check_success version-check "${{ needs.version-check.result }}"
+          check_success build-cog "${{ needs.build-cog.result }}"
+          check_success build-sdk "${{ needs.build-sdk.result }}"
+          check_success build-rust "${{ needs.build-rust.result }}"
+          check_success fmt-go "${{ needs.fmt-go.result }}"
+          check_success fmt-rust "${{ needs.fmt-rust.result }}"
+          check_success fmt-python "${{ needs.fmt-python.result }}"
+          check_success check-llm-docs "${{ needs.check-llm-docs.result }}"
+          check_success check-stubs "${{ needs.check-stubs.result }}"
+          check_success lint-go "${{ needs.lint-go.result }}"
+          check_success lint-rust "${{ needs.lint-rust.result }}"
+          check_success lint-rust-deny "${{ needs.lint-rust-deny.result }}"
+          check_success lint-python "${{ needs.lint-python.result }}"
+          check_success lint-docs "${{ needs.lint-docs.result }}"
+          check_success test-go "${{ needs.test-go.result }}"
+          check_success fuzz-go "${{ needs.fuzz-go.result }}"
+          check_success test-rust "${{ needs.test-rust.result }}"
+          check_success test-python "${{ needs.test-python.result }}"
+          check_success test-coglet-python "${{ needs.test-coglet-python.result }}"
+          check_success integration-shards "${{ needs.integration-shards.result }}"
+          check_success test-integration "${{ needs.test-integration.result }}"
+
+          if [ "${{ needs.playground-changes.outputs.changed }}" = "true" ]; then
+            check_success test-playground-e2e "${{ needs.test-playground-e2e.result }}"
+          else
+            if [ "${{ needs.test-playground-e2e.result }}" != "skipped" ]; then
+              echo "::error::Playground integration tests should be skipped when playground sources are unchanged"
+              FAILED=true
+            fi
+          fi
 
           if [ "$FAILED" = "true" ]; then
             echo "::error::Some jobs failed or were cancelled"

.github/workflows/release-build.yaml

@@ -25,7 +25,7 @@ on:
     tags: ["v[0-9]+.[0-9]+.[0-9]+*"]
 
 permissions:
-  contents: write
+  contents: read
 
 env:
   CARGO_TERM_COLOR: always
@@ -248,6 +248,25 @@ jobs:
           name: sdk-dist
           path: dist/*
 
+  build-playground:
+    name: Build playground assets
+    needs: verify-tag
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/checkout@v6
+      - uses: jdx/mise-action@v4
+        with:
+          version: 2026.4.27
+          cache_key_prefix: mise-rel-${{ github.job }}
+      - name: Build embedded playground assets
+        run: mise run --force build:playground
+      - name: Upload playground assets
+        uses: actions/upload-artifact@v6
+        with:
+          name: playground-assets
+          path: pkg/cli/playground
+
   build-coglet-wheels:
     name: Build coglet wheel (${{ matrix.target }})
     needs: verify-tag
@@ -298,7 +317,9 @@ jobs:
 
   create-release:
     name: Create release
-    needs: [verify-tag, build-sdk, build-coglet-wheels]
+    permissions:
+      contents: write
+    needs: [verify-tag, build-sdk, build-coglet-wheels, build-playground]
     # macOS arm64 runner: native clang for darwin targets, zig for linux targets.
     # CGo required for go-tree-sitter (static Python schema parser).
     runs-on: macos-14
@@ -327,6 +348,12 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
+      - name: Download verified playground assets
+        uses: actions/download-artifact@v8
+        with:
+          name: playground-assets
+          path: pkg/cli/playground
+
       # Goreleaser builds CLI binaries and creates draft release
       - name: Build CLI and create draft release
         uses: goreleaser/goreleaser-action@v7

.gitignore

@@ -58,3 +58,10 @@ target
 
 # Generated docs
 /site
+
+# Playground frontend
+/playground/node_modules/
+/playground/coverage/
+/playground/playwright-report/
+/playground/test-results/
+/pkg/cli/playground/

.golangci.yaml

@@ -64,6 +64,8 @@ linters:
         - weakCond
   exclusions:
     generated: strict
+    paths:
+      - playground/node_modules
     rules:
       # Exclude some linters from running on test files
       - path: '(.+)_test\.go'