Chapter 4

Sync + Offline

Mobile + desktop sync to the same API.

~25 min total3 lessonsAssignment

By the end of this chapter you'll be able to

Mobile offline reads
Desktop outbox
Resolve conflicts

Lessons

Module: Offline

Mobile offline

React Query persistence.

8mmedium

Desktop outbox

Queue + push + pull.

9mhard

Conflict resolution

Last-write-wins vs. CRDT-light.

8mhard

Chapter assignment

Survive a flaky network

Toggle airplane mode on mobile + desktop while the user is mid-flow. Confirm both keep working (offline reads + queued writes). Re-enable network. Confirm both flush their queues and converge to the same state without manual refresh.

See success criteria

Lesson 1 takes ~8 min.

Start chapter

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ch.3: Building a Feature Across All Three ch.5: Coordinated Releases