Architecture

The synctable runtime has six layers, each owned by one package. Data flows bottom-up through the database engine, out through the sync protocol, and into the local-first client.

System diagram

Browser (React hooks, Dexie+Zustand)
        |  hint-then-fetch
Hono Server (/sync, /hints, /trace, /commit)
        |  coalesced hints, fetch_since, SSE
@synctable/server (admin stream, 7-hop trace, OTel)
        |  outbox drain
@synctable/core (Postgres: catalog, capture, applier, DAG, outbox, NOTIFY)

Components

Package	Role
@synctable/core	Authoring API, codegen, reverse projection, Drizzle plugin
@synctable/server	Hono router factory, sync protocol, subscriber, OTel
@synctable/client	Dexie persistence, Zustand store, command queue, reconcile worker

Design decisions

Target is a table, not a native MATERIALIZED VIEW — tables can be triggered, replicated, and partially updated.
Change gate at capture time — unwatched columns never enqueue the view.
Two delivery paths: NOTIFY (in-cluster doorbell) + outbox (durable, ordered cursor).
Auth-scope column in every key — deltas cannot cross tenant boundaries.