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Continuous integration

Jest E2E is CI-ready by default: when CI=true (set automatically by GitHub Actions and most CI providers), tests run headless with a fixed 1280×720 viewport and step logging disabled.

GitHub Actions​

.github/workflows/e2e.yml
name: E2E tests

on: [push, pull_request]

jobs:
  e2e:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: 20
          cache: npm
      - run: npm ci
      - run: npx jest-e2e --retries 2

      # Failure screenshots make CI failures diagnosable
      - uses: actions/upload-artifact@v4
        if: failure()
        with:
          name: screenshots
          path: __screenshots__/

Recommendations​

Upload __screenshots__/ on failure. Every failed test saves a full-page screenshot — in CI this is your only window into what the browser saw.

Use retries in CI, sparingly. --retries 2 absorbs one-off network blips. If a test needs retries to pass consistently, fix the test.

Pin timeouts to your app, not to hope. If your slowest page takes 8 seconds to settle, set the auto-wait timeout above it once:

npx jest-e2e --timeout 15000

Run headless locally too before pushing:

npm run test:headless

Environment variables​

VariableEffect
CI=trueHeadless browser, fixed viewport, steps off
JEST_E2E_TIMEOUT=<ms>Auto-wait timeout for actions and assertions
JEST_E2E_RETRIES=<n>Retry failed tests n times
JEST_E2E_SCREENSHOT=falseDisable failure screenshots
VERCEL_AUTOMATION_BYPASS_SECRET=<secret>Send Vercel Deployment Protection bypass headers automatically
JEST_E2E_AUTH_HEADER_NAME=<name>Generic automation auth header name
JEST_E2E_AUTOMATION_KEY=<secret>Generic automation auth header value
JEST_E2E_AUTH_HEADERS='{"x-api-key":"secret"}'Generic auth headers as JSON
JEST_E2E_AUTH_QUERY_PARAMS='{"preview":"1"}'Generic auth query params as JSON
JEST_E2E_AUTH_COOKIES='[{"name":"session","value":"secret"}]'Generic auth cookies as JSON
JEST_E2E_CONFIG=path/to/config.jsUse a custom project config file
JEST_SILENT=trueSuppress step logging entirely
JEST_FORCE_STEPS=trueForce step logging on in CI

The CLI flags set these for you; use the variables directly when invoking Jest without the CLI.