Self-hosted collaborative sync backend with a portable CRDT core.
crdtsync.com · part of the faiscadev org
This project is in early design. Nothing here is shippable yet. The architecture, primitives, schema language, and APIs are still being finalized. Wire format and op envelope are explicitly not locked yet — see ARCHITECTURE.md → Foundational Decisions for what's still open.
If you stumbled here looking for a working collaborative sync engine: come back later, or use Yjs / Automerge / Liveblocks in the meantime.
A realtime collaborative sync backend + portable CRDT engine, designed around:
- Batteries-included deployment — single container, no Postgres / Redis / Kafka / NATS / etc. required
- Portable CRDT core — one OCaml implementation, exported as WASM (browser/Node) and stable C ABI (native bindings for Python / Go / Rust / JVM)
- Multi-language SDKs that all edit the same document natively
- First-class everything — schema, invariant repair, schema migration, undo/redo, named versions, branches, authorization (with wire-level redaction), awareness — all built into core rather than left for apps to reinvent
- Not "yet another CRDT library." The differentiation is the infrastructure around CRDTs (deployment, scaling, schema, auth, versioning), not the data structures themselves.
- Not a hosted SaaS. Self-hosted first.
- Not a Yjs fork. Yjs interop is via a one-way snapshot importer (
fromYDoc), not wire-protocol compatibility.
┌───────────────────┐
│ Client SDKs │
│ JS / Python / Go │
│ / Rust / JVM │
└─────────┬─────────┘
│
▼
┌───────────────────┐
│ Shared CRDT Core │
│ OCaml │
└─────────┬─────────┘
│
┌───────────────┴───────────────┐
▼ ▼
WASM Export C ABI Export
│ │
▼ ▼
Browser / Node Native language bindings
┌───────────────────┐
│ Sync Server │
│ OCaml │
└─────────┬─────────┘
│
▼
┌───────────────────┐
│ Embedded Storage │
│ SQLite / RocksDB │
└───────────────────┘
This is a monorepo. Core + SDKs + adapters + CLI + website all live together. See MONOREPO.md for layout and contributing guidance.
| File | Purpose |
|---|---|
| README.md | This file — project overview |
| ROADMAP.md | High-level milestones (v0.1 through v0.7) |
| KANBAN.md | Detailed task breakdown for the current milestone |
| MONOREPO.md | Repository layout, build conventions, release process |
| ARCHITECTURE.md | Full design spec — primitives, schema, auth, migrations, branches, awareness, foundational decisions |
AGPL-3.0-or-later. See LICENSE.
- Issues & discussions: this repo (GitHub)
- Site: crdtsync.com (coming)