Electric Sql

ElectricSQL makes PostgreSQL data instantly available client-side — define a "shape" (a filtered view of a Postgres table), and ElectricSQL syncs it to local SQLite in the browser or mobile app in real time. For agents: embed a local SQLite database in agent interfaces that need to work offline, sync agent configuration or state from a Postgres backend without polling APIs, and enable real-time collaborative agent workspaces with automatic conflict resolution. ElectricSQL Electric v2 (2024) uses HTTP long-polling for sync (no WebSocket dependency). Confidence is docs-derived.

TypeScript SDK: npm install electric-sql. Sync shape: import { Shape } from "@electric-sql/client"; const shape = new Shape({ url: "http://electric-host/v1/shape/todos?table=todos&where=user_id%3D123", backoffOptions: {...} }). Subscribe: shape.subscribe(({ rows }) => { setTodos(rows); }). React hook: import { useShape } from "@electric-sql/react"; const { data: todos } = useShape({ url: "http://electric-host/v1/shape/todos" }). HTTP API (Electric server): GET /v1/shape/{shape_name}?table={table}&where={filter}&offset={offset} returns shape data as JSON. SSE: streaming updates via If-None-Match + handle: headers. Shape params: table (required), where (SQL WHERE clause), columns (subset of columns). Local SQLite write: through your own application code + sync back to Postgres via standard API.

Electric server auth: configurable per deployment (proxy Electric behind your own auth layer). Electric Cloud: API key or JWT. HTTPS enforced. Shape access control: filter shapes by user ID in where clause + validate server-side. No built-in auth in the Electric HTTP API — must proxy through authenticated API gateway. JWT-based auth available in Electric v2 for shape access control. Self-hosted: manage auth at reverse proxy level.

Sync latency: shapes update within seconds of Postgres writes. Offline: local SQLite reads work without network; writes queue for sync on reconnect (v2: optimistic updates via local writes). Conflict resolution: last-writer-wins for simple cases; CRDT-based for collaborative scenarios. Shape invalidation: if where clause changes, Electric issues a must-refetch signal. Large shapes: shapes stream incrementally — initial sync proportional to shape size. Electric server: stateless (can scale horizontally behind load balancer). Postgres dependency: Electric requires Postgres with logical replication enabled. Self-hosted: Docker + Postgres with wal_level=logical.

electric-sql.com/docs covers shape definition guide, TypeScript SDK reference, React integration, HTTP API specification, and self-hosting with Docker. Getting started: npm install @electric-sql/react — connect to Electric Cloud or self-hosted in 5 minutes. Electric Cloud: free tier. Self-hosted: Docker + Postgres. GitHub: electric-sql/electric (7k+ stars). Community via Discord (active). Good documentation; shape concept is well-explained with visual diagrams.