Offline should be the norm: building local-first apps with CRDTs & Kotlin Multiplatform

on YouTube ↗45m

" summary

Argues that offline should be the norm and proves it with a working Kotlin Multiplatform app that shares a sync core across Android iOS and Web, using a Ktor server for demos, CRDTs converge by construction, and a concrete stack: OR-Set + LWW register + delta buffer for merges and tombstone pruning. Shows the shopping list demo where concurrent edits merge without manual conflict, discusses vector clocks pruning and UI glitch mitigation, and reports the approach works end to end.

AI-written summary · about

" chapters (12)

1. 0:00Introduction
2. 3:55Local-first app example
3. 8:09Offline-first principles
4. 12:19Sync strategies
5. 17:58Offline reads and writes
6. 20:52Conflict resolution with CRDTs
7. 23:19CRDT mathematics
8. 31:30Kotlin Multiplatform CRDTs
9. 36:29Delta sync demo
10. 38:59CRDT challenges
11. 40:24Why offline should be the norm
12. 41:34Q&A

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