SQLite or PostgreSQL

Arenile works with SQLite (default) or PostgreSQL, with the same code and the same guarantees: every integration and concurrency test runs on both.

SQLite (default)

One file (/data/arenile.db) in WAL mode, no extra service to run, backups with one command. Ideal for one or a few establishments: a whole beach, with desk, beach staff and online bookings at the same time, is a light load for SQLite.

PostgreSQL

Recommended with many establishments in the same installation, with several Arenile instances in parallel, or if you already have a managed PostgreSQL with backups and monitoring. Enabled with DATABASE_URL.

What does not change

No double selling on either: the uniqueness of a spot per date and slot is a database constraint, and quantity counters use conditional updates, identical in both dialects.
Same features, same APIs, same migrations (one pair for each schema version).
Calendar dates as YYYY-MM-DD, instants in UTC, amounts in integer cents.

What changes

	SQLite	PostgreSQL
Services to run	none	a PostgreSQL server
Backup	`arenile backup --out FILE`	`pg_dump` / `pg_restore`
Several Arenile instances	no	possible (real time across instances needs an `EventBus` extension)
Variable	none	`DATABASE_URL=postgres://...`

Enabling PostgreSQL

DATABASE_URL=postgres://arenile:password@db:5432/arenile?sslmode=disable

Or use deploy/docker-compose.postgres.yml directly, which starts PostgreSQL 17 and sets DATABASE_URL for you (see Install with Docker).

Moving from SQLite to PostgreSQL

Moving an existing installation is not automatic. The safest way is to do it off season: export the data you need, start a new installation on PostgreSQL and re-create the configuration. If you run a single beach, staying on SQLite is almost always the best choice.