paperclip/docs/deploy/database.md

title	summary
Database	Embedded PGlite vs Docker Postgres vs hosted

Paperclip uses PostgreSQL via Drizzle ORM. There are three ways to run the database.

1. Embedded PostgreSQL (Default)

Zero config. If you don't set DATABASE_URL, the server starts an embedded PostgreSQL instance automatically.

pnpm dev

On first start, the server:

1. Creates ~/.paperclip/instances/default/db/ for storage
2. Ensures the paperclip database exists
3. Runs migrations automatically
4. Starts serving requests

Data persists across restarts. To reset: rm -rf ~/.paperclip/instances/default/db.

The Docker quickstart also uses embedded PostgreSQL by default.

2. Local PostgreSQL (Docker)

For a full PostgreSQL server locally:

docker compose up -d

This starts PostgreSQL 17 on localhost:5432. Set the connection string:

cp .env.example .env
# DATABASE_URL=postgres://paperclip:paperclip@localhost:5432/paperclip

Push the schema:

DATABASE_URL=postgres://paperclip:paperclip@localhost:5432/paperclip \
  npx drizzle-kit push

3. Hosted PostgreSQL (Supabase)

For production, use a hosted provider like Supabase.

1. Create a project at database.new
2. Copy the connection string from Project Settings > Database
3. Set DATABASE_URL in your .env

Use the direct connection (port 5432) for migrations and the pooled connection (port 6543) for the application.

If using connection pooling (transaction mode), disable prepared statements via the environment — no source edits needed:

DATABASE_PREPARED_STATEMENTS=false

Related optional client tuning: DATABASE_POOL_MAX, DATABASE_IDLE_TIMEOUT_SECONDS, DATABASE_CONNECT_TIMEOUT_SECONDS, DATABASE_MAX_LIFETIME_SECONDS, DATABASE_APPLICATION_NAME. Driver defaults apply when unset, except that idle pooled connections close after 60 seconds (DATABASE_IDLE_TIMEOUT_SECONDS=0 keeps them open) and the pool reports application_name=paperclip. See Connection pool settings.

Connection Pool Settings

The server opens one postgres.js pool for its own queries (and a second one when DATABASE_MIGRATION_URL points at a different connection). Every setting is optional:

Variable	Default	Effect
DATABASE_POOL_MAX	10 (driver)	Maximum pooled connections.
DATABASE_IDLE_TIMEOUT_SECONDS	60	Close a pooled connection after this much idle time. 0 keeps idle connections open forever (the driver default).
DATABASE_CONNECT_TIMEOUT_SECONDS	30 (driver)	Give up on a connection attempt after this long.
DATABASE_MAX_LIFETIME_SECONDS	30–60 min, randomized (driver)	Recycle a pooled connection once it is this old.
DATABASE_APPLICATION_NAME	paperclip	Value of application_name in pg_stat_activity, so you can find Paperclip's backends: SELECT * FROM pg_stat_activity WHERE application_name = 'paperclip';
DATABASE_PREPARED_STATEMENTS	true (driver)	Set false behind a transaction-mode pooler (see above).

The server ends its pools during shutdown (SIGINT/SIGTERM) and when startup fails after the pool was opened, so a restarting server does not leave idle backends behind. Size max_connections on the PostgreSQL side for at least DATABASE_POOL_MAX per server process plus your other clients.

Switching Between Modes

DATABASE_URL	Mode
Not set	Embedded PostgreSQL
postgres://...localhost...	Local Docker PostgreSQL
postgres://...supabase.com...	Hosted Supabase

The Drizzle schema (packages/db/src/schema/) is the same regardless of mode.