alt Hacker NewsShow HN: SyncKit – Offline-first sync engine (Rust/WASM and TypeScript)
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I think I know what this is, but the description is so much in its own context I'm not sure. It's for web-apps that also want an offline local version that works and deals with syncing the data when online again and either local or remote is updated?
It probably markets and explains itself perfectly find for someone in that space and/or looking for this solution, so I'm not sure that's actually a problem, but if you also want to stick in the mind of someone that sees this and doesn't have any current interest, but may stumble into needing a solution like this in the future, a few extra words in your initial description might help it be understood more quickly and be something remembered even if they don't dive into it. Or maybe it's fine and I'm just a bit slow today.
The conflict resolution guide seems quite clear:
https://github.com/Dancode-188/synckit/blob/main/docs/guides...
But I’m a little confused about why it says “Zero data loss with automatic conflict resolution” on the top level page and “data loss possible” under the disadvantages of last-write-wins conflict resolution. It makes sense that you have to start somewhere, but to my mind, last-write-wins isn’t really conflict resolution? What does using this library solve?
I guess it means edits to different fields don’t conflict. But if it’s the same field, it will get clobbered.
Hey HN, I built SyncKit after shipping two local-first projects (RestBolt and Graft) and realizing there's no simple way to add cross-device sync.
The problem: Existing solutions are either too complex (Automerge/Yjs require learning CRDTs) or too restrictive (Firebase isn't truly local-first, Supabase has no offline support - issue #357 has been open 4+ years with 350+ upvotes).
SyncKit is the middle ground: simple API, works offline-first, self-hostable.
Technical highlights: - TLA+ formal verification: 118,711 states checked, caught bugs before implementation - Rust → WASM core (48.9KB gzipped) - 700+ tests including 80 chaos tests (zero data loss) - Server: Bun/Hono WebSocket (SDK works in any JS runtime) - Production-ready: v0.1.0 on npm and Docker Hub
Known limitations (v0.1.0): - LWW only - advanced CRDTs (Text, Counter, Set) coming in v0.2.0 - React hooks only - Vue/Svelte adapters planned - Reference server is Bun (Node/Deno coming v0.3.0)
Happy to answer questions about the CRDT implementation, TLA+ modeling, or WebSocket architecture.
GitHub: https://github.com/Dancode-188/synckit npm: @synckit-js/sdk
When you mentioned offline sync and graft, I mistook you for the author of this project:
https://github.com/orbitinghail/graft
However, they're clearly two different projects.
I don't want to take away from the work you've done, as you're clearly knowledgeable, but as someone else observed, heavy use of AI assistance can be observed in all your public projects. It's worth explicitly addressing, especially considering the foundational nature of your project: it's not easily replaced if it turns out to have to have subtle bugs.
Though I rarely use it myself, I'd like to know, simply because I'm curious as to how other engineers have incorporated such assistance it into their process.
Based on the commits(especially the early/foundational ones) this seems to be built primarily with Claude, but I don't see that mentioned in the README.
This is impressive! After Realm depreciation I have been trying many different offline sync options, they are especially few on Dart… Dart-Rust binding generator is pretty great though so it’s nice this is in Rust. Will keep an eye on this.
Always nice to see something in here. Would love to hear what is your take on https://www.instantdb.com/?
Good work @danbitengo Is this usable in native Android app development?
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I want to create a local first, offline/p2p realtime multiplayer prototype app soon with reactive/signal data model and frontend agnostic design (considering solidjs/svelte). I'm on a tech research stage. How does it compare to rxdb, tinybase and zero sync? For reference right now I'm considering tinydb/rxdb.