Zero

What is Zero?

Zero is a query-driven sync engine for TypeScript applications. It runs zero-cache next to Postgres, maintains a SQLite replica, and syncs the rows your app queries to connected clients for fast local-first reads and writes.

Notes on deployment

The Coolify service template deploys zero-cache with a PostgreSQL database configured for logical replication. You still need to deploy your own frontend and API server separately, then point Zero at the API endpoints that implement your query and mutation handlers.

The template requires these environment variables before deployment:

• ZERO_QUERY_URL: URL of your API /query endpoint.
• ZERO_MUTATE_URL: URL of your API /mutate endpoint.

The template also creates these automatically:

• ZERO_ADMIN_PASSWORD: generated by Coolify and used for Zero admin endpoints such as /statz and the inspector.
• ZERO_UPSTREAM_DB, ZERO_CVR_DB, and ZERO_CHANGE_DB: point to the bundled PostgreSQL service.
• ZERO_REPLICA_FILE: stores the SQLite replica on a persistent volume.

Links

• Official website
• Self-hosting documentation
• Configuration reference