Build-an-X workflow for a critical-path smoke suite that runs in <5 minutes - picks the 5-15 highest-business-value journeys (login, hero flow, checkout, payment, primary read), implements as fast E2E or API tests, gates per-deploy, retries on transient failures with quarantine. Use as the canary-precursor or per-deploy verification gate; the team's "if this fails, the build can't proceed" floor.