How do you run Selenium suites reliably in CI?

CI is a different environment from a developer laptop: no display, fresh filesystem, limited CPU and network latency to the application. The pipeline must supply a browser, a target URL and credentials, then preserve enough evidence to debug failures after the runner is gone.

name: e2e
on: [push]
jobs:
  test:
    runs-on: ubuntu-latest
    timeout-minutes: 30
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-java@v4
        with:
          distribution: temurin
          java-version: "21"
      - run: mvn -B test
      - uses: actions/upload-artifact@v4
        if: always()
        with:
          name: test-reports
          path: target/surefire-reports

• Use headless browsers or a Grid rather than expecting a display server
• Pin browser and driver versions so CI does not change underneath the suite
• Provide the application URL and credentials through environment variables or secrets
• Always upload reports and screenshots, including on failure
• Set a job timeout so a hung browser cannot block the queue indefinitely
• Shard or parallelise only after the suite is stable

A common CI failure is a test that assumes a local service or a developer's data. Start the application or point at a dedicated test environment explicitly, and wait for its health check before running tests. Network latency in CI is often higher than locally, so timeouts must reflect that environment.