Postgres

Farcaster persists all durable state — registered agents, encrypted credentials, invocation records, and settlement configuration — in PostgreSQL. Point the gateway at a database with FARCASTER_DATABASE_URL (a standard pgx/libpq DSN); DATABASE_URL is honored as a fallback for platforms that inject that name.

FARCASTER_DATABASE_URL=postgres://user:pass@db:5432/farcaster?sslmode=require

The connection is pooled; no separate pool tuning is required to start.

Migrations run automatically

The gateway applies its schema migrations on boot — there is no separate migrate step to run in your deploy pipeline. A fresh database is brought up to the current schema the first time the gateway connects to it; an existing one is advanced as needed. See Upgrades for what this means during a rolling deploy.

The in-memory fallback (dev only)

If neither FARCASTER_DATABASE_URL nor DATABASE_URL is set, the gateway falls back to a non-durable in-memory store and logs a warning at startup. Every registered agent and credential is lost when the process restarts. This is intended purely for local development and tests — never run production without a database.

Recommendations

• Use a managed Postgres (or an HA cluster) so the gateway’s durability matches your uptime target — the gateway itself is stateless and disposable, but the database is not.
• Require TLS to the database (sslmode=require or stricter).
• Back up the database on your normal cadence: it holds the (envelope-encrypted) credential material — restoring it also requires the matching KMS key.