Adam Fish (Ditto) - CRDTS Solved Conflicts, Not Sync

The sync community has obsessed over CRDTs and conflict resolution for years. But conflict-free replication is just table stakes—it solves merge conflicts, not correctness under queries. The real challenge isn't making data converge; it's making queries stay correct across unreliable and inconsistent networks.Most CRDT systems retransmit entire objects or documents on every change. This breaks down at scale, especially in bandwidth-constrained environments where deskless workers operate. True resilience requires rethinking propagation entirely: property-level diffs, query-based synchronization, and incremental re-evaluation that keeps clients consistent without transferring full datasets. This technical deep dive explores what comes after conflict-free replication: Why CRDTs solve conflicts but not query consistency at scale Property-level diffs and query-based propagation vs. document retransmission Incremental query re-evaluation: keeping clients correct without the full dataset Multihop, multiplexed replication for maintaining query liveness in mesh topologies Distributed access control in query-consistent systems We'll examine the architectural shift from "synchronization as an operation" to systems that simply converge—and why this matters for production deployments where networks are unreliable and queries need to stay correct. ---- Software UX, DX, and AX are all being redefined and reinvented as we speak. The next generation of products are being built on sync engines and local-first architectures, enabling realtime collaboration between humans and agents. Learn from developers at the world's leading startups on how they use these technologies. Find out what you and your team need to know in building category-defining products. -- Join our discord!   / discord   --- Subscribe for more talks: @localfirstconf Follow: https://x.com/sync_conf Visit: https://syncconf.dev/ --- Thanks to our wonderful sponsors: Cloudflare - https://workers.cloudflare.com/ PowerSync - https://www.powersync.com/ Jazz - https://jazz.tools/ Ditto - https://www.ditto.com/ VAPI - https://vapi.ai/ tldraw - https://www.tldraw.com/ Convex - https://www.convex.dev/ Neon - https://neon.com/ Daytona - https://www.daytona.io/ --- Thanks to https://moat-studio.com/ & https://www.kurtelavideo.com/ for the videos!