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(Compiler) Playground workflow (facebook/react)

The (Compiler) Playground workflow from facebook/react, explained and optimized by Latchkey.

C

CI health: C - fair

The optimized version below adds caching, job timeouts.

Source: facebook/react.github/workflows/compiler_playground.ymlLicense MITView source

What it does

This is the (Compiler) Playground workflow from the facebook/react repository, a real project running GitHub Actions. It is shown here with attribution under its MIT license.

Below, Latchkey shows a faster, safer version produced by its optimization engine.

The workflow

workflow (.yml)
name: (Compiler) Playground

on:
  push:
    branches: [main]
  pull_request:
    paths:
      - compiler/**
      - .github/workflows/compiler_playground.yml

permissions: {}

concurrency:
  group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
  cancel-in-progress: true

env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
  # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
  SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1

defaults:
  run:
    working-directory: compiler/apps/playground

jobs:
  playground:
    name: Test playground
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
      - name: Cache node_modules
        uses: actions/cache@v4
        id: node_modules
        with:
          path: |
            **/node_modules
          key: compiler-and-playground-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
      - run: yarn install --frozen-lockfile
        if: steps.node_modules.outputs.cache-hit != 'true'
        working-directory: compiler
      - run: yarn install --frozen-lockfile
        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Check Playwright version
        id: playwright_version
        run: echo "playwright_version=$(npm ls @playwright/test | grep @playwright | sed 's/.*@//' | head -1)" >> "$GITHUB_OUTPUT"
      - name: Cache Playwright Browsers for version ${{ steps.playwright_version.outputs.playwright_version }}
        id: cache_playwright_browsers
        uses: actions/cache@v4
        with:
          path: ~/.cache/ms-playwright
          key: playwright-browsers-v6-${{ runner.arch }}-${{ runner.os }}-${{ steps.playwright_version.outputs.playwright_version }}
      - run: npx playwright install --with-deps chromium
        if: steps.cache_playwright_browsers.outputs.cache-hit != 'true'
      - run: CI=true yarn test
      - run: ls -R test-results
        if: '!cancelled()'
      - name: Archive test results
        if: '!cancelled()'
        uses: actions/upload-artifact@v4
        with:
          name: test-results
          path: compiler/apps/playground/test-results
          if-no-files-found: ignore

The same workflow, on Latchkey

Estimated ~20% faster on cache hits, plus fewer wasted runs and a safer supply chain. Added and changed lines are highlighted.

name: (Compiler) Playground on:  push:    branches: [main]  pull_request:    paths:      - compiler/**      - .github/workflows/compiler_playground.yml permissions: {} concurrency:  group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}  cancel-in-progress: true env:  TZ: /usr/share/zoneinfo/America/Los_Angeles  # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout  SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1 defaults:  run:    working-directory: compiler/apps/playground jobs:  playground:    timeout-minutes: 30    name: Test playground    runs-on: latchkey-small    steps:      - uses: actions/checkout@v4      - uses: actions/setup-node@v4        with:          cache: 'npm'          node-version-file: '.nvmrc'      - name: Cache node_modules        uses: actions/cache@v4        id: node_modules        with:          path: |            **/node_modules          key: compiler-and-playground-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}      - run: yarn install --frozen-lockfile        if: steps.node_modules.outputs.cache-hit != 'true'        working-directory: compiler      - run: yarn install --frozen-lockfile        if: steps.node_modules.outputs.cache-hit != 'true'      - name: Check Playwright version        id: playwright_version        run: echo "playwright_version=$(npm ls @playwright/test | grep @playwright | sed 's/.*@//' | head -1)" >> "$GITHUB_OUTPUT"      - name: Cache Playwright Browsers for version ${{ steps.playwright_version.outputs.playwright_version }}        id: cache_playwright_browsers        uses: actions/cache@v4        with:          path: ~/.cache/ms-playwright          key: playwright-browsers-v6-${{ runner.arch }}-${{ runner.os }}-${{ steps.playwright_version.outputs.playwright_version }}      - run: npx playwright install --with-deps chromium        if: steps.cache_playwright_browsers.outputs.cache-hit != 'true'      - run: CI=true yarn test      - run: ls -R test-results        if: '!cancelled()'      - name: Archive test results        if: '!cancelled()'        uses: actions/upload-artifact@v4        with:          name: test-results          path: compiler/apps/playground/test-results          if-no-files-found: ignore 

What changed

  • Run on Latchkey managed runners with one line (runs-on), which apply the fixes below automatically and self-heal transient failures. This example uses latchkey-small; pick the runner size that fits the job.
  • Cache dependency installs on the setup step so they are served from cache.
  • Add a job timeout so a hung step cannot burn hours of runner time.

What Latchkey heals here

This workflow has steps that commonly fail on transient issues (network, registries, flaky browsers). On Latchkey managed runners they are detected, retried, and self-healed instead of failing your build:

  • Dependency installs
  • End-to-end and browser tests

This workflow runs 1 job per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow

Frequently asked questions

What does the (Compiler) Playground workflow (facebook/react) workflow do?
This is the (Compiler) Playground workflow from the facebook/react repository, a real project running GitHub Actions. It is shown here with attribution under its MIT license.
What CI health grade does this workflow get?
This Node.js workflow grades C. Paste your own workflow into the Latchkey grader to see its grade and the exact fixes.
How can I improve this Node.js workflow?
Apply caching, job timeouts. Latchkey applies these automatically on managed runners when you point runs-on at Latchkey.

References