Building a real-time collaboration tool using CRDTs and Kotlin Multiplatform

on YouTube ↗39m

" summary

A real-time collaborative board is built using CRDTs and a Kotlin Multiplatform core library shared across Android, iOS, web and backend, syncing over websockets with offline persistence. Conflict resolution uses hybrid logical clocks for ordering, grow-only sets plus tombstones for deletions, fractional (base-63) Z indices for infinite ordering, and external image uploads with grow-only layer readiness. The Microsoft Teams web client and mobile apps run and sync correctly in production.

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" chapters (10)

1. 0:00Introduction and agenda
2. 1:52About Bontouch and Postit app
3. 3:37Need for real-time sync and CRDTs
4. 5:03CRDTs properties and benefits
5. 8:51Hybrid logical clocks explained
6. 15:14Implementing CRDTs in Kotlin
7. 20:37Data model design challenges
8. 27:40Kotlin Multiplatform choice
9. 35:03Key learnings and takeaways
10. 38:59Q&A and closing

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