# Lesson 4 complete; primaries still deferred

Learner finished deal-breakers: wrong-tool redirects, versioning/no-expiry, opaque/CORS, dual HTTP+SW cache layers, quota/eviction/Safari caps. External primaries remain unread (lesson-first path). Next: decision playbook as mission payoff — synthesize store + strategy + one owned risk into a design-review sentence without requiring external reads.