[FEATURE glimmer-next-demo] Demo app for glimmer-next renderer

.github/workflows/ci-jobs.yml

@@ -87,8 +87,11 @@ jobs:
         run: pnpm vite build --mode=development
         env:
           NODE_ENV: development
+          GXT_MODE: 'true'
       - name: test
         run: pnpm test
+        env:
+          GXT_MODE: 'true'
 
   variant-tests:
     name: ${{ matrix.name }}
@@ -123,12 +126,14 @@ jobs:
         run: pnpm vite build --mode=${{ matrix.BUILD || 'development' }}
         env:
           NODE_ENV: ${{ matrix.BUILD || 'development' }}
+          GXT_MODE: 'true'
       - name: test
         env:
           ALL_DEPRECATIONS_ENABLED: ${{ matrix.ALL_DEPRECATIONS_ENABLED }}
           OVERRIDE_DEPRECATION_VERSION: ${{ matrix.OVERRIDE_DEPRECATION_VERSION }}
           ENABLE_OPTIONAL_FEATURES: ${{ matrix.ENABLE_OPTIONAL_FEATURES }}
           RAISE_ON_DEPRECATION: ${{ matrix.RAISE_ON_DEPRECATION }}
+          GXT_MODE: 'true'
 
         run: pnpm test
 

.github/workflows/gxt-dual-build.yml

@@ -0,0 +1,42 @@
+name: GXT dual-build matrix
+
+on:
+  push:
+    branches:
+      - master
+      - main
+      - glimmer-next-fresh
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    name: Build ${{ matrix.backend }}
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+    strategy:
+      fail-fast: false
+      matrix:
+        backend: [classic, gxt]
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+      - uses: ./.github/actions/setup
+      - name: Build (${{ matrix.backend }})
+        run: |
+          rm -rf dist
+          if [ "${{ matrix.backend }}" = "gxt" ]; then
+            EMBER_RENDER_BACKEND=gxt npx rollup --config rollup.config.mjs
+          else
+            npx rollup --config rollup.config.mjs
+          fi
+      - name: Upload dist artifact
+        if: always()
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: dist-${{ matrix.backend }}
+          path: dist/prod/packages/
+          if-no-files-found: warn

.github/workflows/gxt-full.yml

@@ -0,0 +1,77 @@
+name: GXT Full (nightly)
+
+on:
+  schedule:
+    - cron: '0 6 * * *'
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  issues: write
+
+jobs:
+  gxt-full:
+    name: GXT full suite
+    runs-on: ubuntu-latest
+    timeout-minutes: 180
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+      - uses: ./.github/actions/setup
+      - name: Install Playwright browsers
+        run: pnpm exec playwright install --with-deps chromium
+      - name: Run GXT full suite vs baseline
+        id: gxt-run
+        env:
+          GXT_MODE: 'true'
+        run: |
+          node scripts/gxt-test-runner/runner.mjs \
+            --full \
+            --auto-serve \
+            --url http://localhost:5180/ \
+            --baseline test-results/gxt-baseline.json
+      - name: Upload run artifacts
+        if: always()
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: gxt-full-run
+          path: |
+            test-results/gxt-summary.json
+            test-results/gxt-last-run.json
+          if-no-files-found: ignore
+      - name: Upload candidate baseline
+        if: always()
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: gxt-candidate-baseline
+          path: test-results/gxt-summary.json
+          if-no-files-found: ignore
+      - name: File regression issue
+        if: failure() && steps.gxt-run.outcome == 'failure'
+        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
+        with:
+          script: |
+            const title = `GXT nightly regression on ${context.sha.substring(0,7)}`;
+            const body = [
+              'The nightly GXT full-suite run failed against',
+              '`test-results/gxt-baseline.json`.',
+              '',
+              `- commit: ${context.sha}`,
+              `- run: https://github.com/${context.repo.owner}/${context.repo.repo}/actions/runs/${context.runId}`,
+              '',
+              'Download the `gxt-full-run` artifact and diff it:',
+              '',
+              '```',
+              'node scripts/gxt-test-runner/diff.mjs \\',
+              '  test-results/gxt-baseline.json \\',
+              '  gxt-summary.json',
+              '```',
+            ].join('\n');
+            await github.rest.issues.create({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              title,
+              body,
+              labels: ['gxt', 'regression', 'nightly'],
+            });

.github/workflows/gxt-smoke.yml

@@ -0,0 +1,60 @@
+name: GXT Smoke
+
+on:
+  push:
+    branches:
+      - master
+      - main
+      - glimmer-next-fresh
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  contract:
+    name: GXT upstream contract
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+      - uses: ./.github/actions/setup
+      - name: Run contract tests
+        run: node scripts/gxt-test-runner/contract-tests.mjs
+
+  gxt-smoke:
+    name: GXT smoke shard ${{ matrix.shard }}/4
+    needs: contract
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    strategy:
+      fail-fast: false
+      matrix:
+        shard: [1, 2, 3, 4]
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+      - uses: ./.github/actions/setup
+      - name: Install Playwright browsers
+        run: pnpm exec playwright install --with-deps chromium
+      - name: Run GXT smoke (shard ${{ matrix.shard }}/4)
+        env:
+          GXT_MODE: 'true'
+        run: |
+          node scripts/gxt-test-runner/runner.mjs \
+            --smoke \
+            --shard ${{ matrix.shard }}/4 \
+            --auto-serve \
+            --url http://localhost:5180/
+      - name: Upload run artifacts
+        if: always()
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: gxt-smoke-shard-${{ matrix.shard }}
+          path: |
+            test-results/gxt-summary.json
+            test-results/gxt-last-run.json
+          if-no-files-found: ignore

.gitignore

@@ -55,3 +55,14 @@ npm-debug.log
 # couple of the files. Once it is, we can switch this over to just ignoring
 # `types/stable` entirely.
 types/stable
+
+# GXT migration debug scripts (ad-hoc, not tracked)
+/scripts/debug-artifacts/
+
+# Ephemeral GXT test outputs (keep baseline + triage)
+/test-results/gxt-last-run.json
+/test-results/gxt-summary.json
+/test-results/rehydration/
+
+# Claude agent working state
+/.claude/

babel.config.mjs

@@ -9,6 +9,8 @@
 import { resolve, dirname } from 'node:path';
 import { fileURLToPath } from 'node:url';
 
+const useGxt = process.env.GXT_MODE === 'true';
+
 export default {
   plugins: [
     [
@@ -24,14 +26,22 @@ export default {
         runtime: { import: 'decorator-transforms/runtime' },
       },
     ],
-    [
-      'babel-plugin-ember-template-compilation',
-      {
-        compilerPath: resolve(
-          dirname(fileURLToPath(import.meta.url)),
-          './broccoli/glimmer-template-compiler.mjs'
-        ),
-      },
-    ],
+    // In GXT mode, template compilation is handled by Vite via the gxt compiler
+    // or templateTag plugin. In classic mode, we must pre-compile
+    // `precompileTemplate` calls here so they don't survive into the runtime
+    // bundle (which would throw at module evaluation time).
+    ...(useGxt
+      ? []
+      : [
+          [
+            'babel-plugin-ember-template-compilation',
+            {
+              compilerPath: resolve(
+                dirname(fileURLToPath(import.meta.url)),
+                './broccoli/glimmer-template-compiler.mjs'
+              ),
+            },
+          ],
+        ]),
   ],
 };

bin/benchmark/run.mjs

@@ -29,7 +29,12 @@ const DEFAULT_EXPERIMENT_PORT = 4501;
 const DEFAULT_FIDELITY = process.env['RUNS'] || '20';
 const DEFAULT_THROTTLE = '1';
 const DEFAULT_REGRESSION_THRESHOLD = '25';
-const DEFAULT_SAMPLE_TIMEOUT = '60';
+// Sample timeout is per-sample wall-clock budget. Upstream commit 19eb4087e6
+// doubled the bench workload (Create5000→Create10000) and added a final
+// clearItems4 phase. Empirically a single sample on the GitHub Actions
+// runner takes ~107-120s on this branch; 120s was too tight (timed out
+// in CI). 240s gives 2× headroom without inflating green-path runtime.
+const DEFAULT_SAMPLE_TIMEOUT = '240';
 const DEFAULT_MARKERS = [
   // Copied from glimmer-vm/bin/setup-bench.mts (krausest benchmark)
   'render',

eslint.config.mjs

@@ -31,6 +31,10 @@ export default [
       'packages/@handlebars/parser/lib/parser.js',
       'packages/@handlebars/parser/src/**',
       'tracerbench-testing/',
+      'packages/@ember/-internals/gxt-backend/**',
+      'packages/demo/**',
+      'scripts/gxt-test-runner/**',
+      'scripts/debug-artifacts/**',
     ],
   },
   pluginJs.configs.recommended,
@@ -231,6 +235,8 @@ export default [
       '**/rollup.config.mjs',
       '**/babel.config.mjs',
       '**/babel.test.config.mjs',
+      '**/vite.config.mjs',
+      'scripts/**/*.mjs',
       'node-tests/**/*.js',
       'tests/node/**/*.js',
       'smoke-tests/node-template/**/*.js',
@@ -260,6 +266,8 @@ export default [
       '**/rollup.config.mjs',
       '**/babel.config.mjs',
       '**/babel.test.config.mjs',
+      '**/vite.config.mjs',
+      'scripts/**/*.mjs',
       'node-tests/**/*.js',
       'tests/node/**/*.js',
       'smoke-tests/node-template/**/*.js',
@@ -293,6 +301,28 @@ export default [
       'disable-features/disable-generator-functions': 'off',
     },
   },
+  {
+    files: ['**/vite.config.mjs', 'scripts/**/*.mjs'],
+    rules: {
+      'no-console': 'off',
+      'n/no-process-exit': 'off',
+      'n/hashbang': 'off',
+      'n/no-unpublished-bin': 'off',
+    },
+  },
+  {
+    // GXT integration scaffolding in core glimmer files: debug logging gated
+    // behind DEBUG_TEMPLATE_LOOKUP / similar runtime flags.
+    files: [
+      'packages/@ember/-internals/glimmer/lib/templates/**/*.ts',
+      'packages/@ember/-internals/glimmer/lib/renderer.ts',
+      'packages/@ember/-internals/glimmer/lib/component-managers/unwrap-template.ts',
+    ],
+    rules: {
+      'no-console': 'off',
+      'no-implicit-coercion': 'off',
+    },
+  },
   {
     files: ['node-tests/**/*.js'],