10.4ADR-004: Fresh Sessions for CI, Reused Named Sessions for Development

Context

The Playwright CLI manages browser sessions in the .playwright-cli/ workspace. Named sessions (-s=name) persist across commands; a session can be closed and a new one opened at any time. The classic trade-off — persistent browser for speed vs fresh browser for isolation — maps onto session lifecycle.

Decision

• Development/local: one long-lived named session, reused across runs — no browser startup cost between iterations, and --headed when you want to watch
• CI/CD: a fresh named session per test for isolation, closed when the test ends

Configuration

# Development: reuse one session all afternoon
playwright-cli -s=dev open https://localhost:3000 --headed
# ... iterate ...

# CI: one session per test, torn down after
playwright-cli -s="$TEST_NAME" open "$BASE_URL/login"
# ... test commands with -s="$TEST_NAME" ...
playwright-cli -s="$TEST_NAME" close

Consequences

• (+) Fast feedback during development
• (+) Clean isolation in CI — no state leaks between tests
• (+) Parallel tests come free: each worker uses its own session name
• (-) Reused dev sessions can accumulate state (mitigated by explicit cleanup: state-save/state-load for known-good baselines, or just close and reopen)