# @briven/realtime — reactive query WebSocket service

per `CLAUDE.md §7.4`:

1. client calls `useQuery("getPosts", { userId })`
2. SDK sends query name + args to realtime over WebSocket
3. realtime computes a query hash, checks cache
4. on miss: invokes query via runtime, caches, returns
5. realtime subscribes to Postgres `LISTEN` channels for every table touched
6. on `NOTIFY` (auto-generated triggers), recompute and push deltas to subscribed clients
7. subscriptions expire when client disconnects

**status: Phase 1 complete (2026-05-09).** wire protocol, refcounted LISTEN/UNLISTEN,
NOTIFY → re-invoke fan-out, channel diffing on `touchedTables`, postgres.js
v3 auto-reattach on reconnect. Caller auth is the runtime shared secret;
SDK-direct connection (per-project JWT) is a Phase 2 follow-up.

year-one scale target: 10,000 concurrent subscriptions. migrate to logical replication + WAL streaming if this becomes a bottleneck.