Map the impact boundary
List changed files, direct consumers, shared contracts, migrations, security boundaries, generated projections, public routes, background work, data lifecycle, and external configuration. Select checks from that map.
Promote one proven candidate through each environment.
A production release should be the exact candidate already proven locally and in staging. Environment-specific configuration changes need their own evidence and must not conceal code drift.
Prove the local environment
Run generator checks, focused unit and integration tests, builds, browser engines, accessibility, JavaScript-disabled initial HTML, crawler behavior, synthetic operating flows, and disposable database cleanup.
Prove staging
Deploy the exact candidate, verify the revision, migrations, workers, health, private-host noindex, public-site noindex, payment test modes, email, storage, observability, backups, rollback, and the complete synthetic journey.
Promote and observe production
Promote the exact staging candidate, verify runtime configuration before traffic, run non-destructive smoke checks, confirm indexing policy, monitor error and queue signals, record evidence, and retain a tested rollback path.