Databases

RomM uses SQLAlchemy + Alembic for persistence. Three drivers are supported, so pick based on what you already run.

Driver	ROMM_DB_DRIVER	Image	Default port	Notes
MariaDB (default, recommended)	mariadb	mariadb:11	3306	What the reference compose uses. Well-tested.
MySQL	mysql	mysql:8	3306	Largely interchangeable with MariaDB for RomM.
PostgreSQL	postgresql	postgres:16	5432	Use if you already run Postgres.

MariaDB (default)

This is what the reference Compose sets up. No extra config beyond filling in the passwords.

services:
    romm:
        environment:
            - ROMM_DB_DRIVER=mariadb
            - DB_HOST=romm-db
    romm-db:
        image: mariadb:11
        environment:
            - MARIADB_ROOT_PASSWORD=<separate-strong-password>
            - MARIADB_DATABASE=romm
            - MARIADB_USER=romm-user
            - MARIADB_PASSWORD=<same-as-DB_PASSWD>
        volumes:
            - mysql_data:/var/lib/mysql
        healthcheck:
            test: ["CMD", "healthcheck.sh", "--connect", "--innodb_initialized"]
            start_period: 30s
            interval: 10s
            timeout: 5s
            retries: 5

MySQL

Identical compose to MariaDB but swap the image and the healthcheck:

services:
    romm:
        environment:
            - ROMM_DB_DRIVER=mysql
            - DB_PORT=3306
    romm-db:
        image: mysql:8
        environment:
            - MYSQL_ROOT_PASSWORD=<separate-strong-password>
            - MYSQL_DATABASE=romm
            - MYSQL_USER=romm-user
            - MYSQL_PASSWORD=<same-as-DB_PASSWD>
        volumes:
            - mysql_data:/var/lib/mysql
        healthcheck:
            test: ["CMD", "mysqladmin", "ping", "-h", "localhost"]
            interval: 10s
            timeout: 5s
            retries: 5

PostgreSQL

services:
    romm:
        environment:
            - ROMM_DB_DRIVER=postgresql
            - DB_PORT=5432
    romm-db:
        image: postgres:16
        environment:
            - POSTGRES_DB=romm
            - POSTGRES_USER=romm-user
            - POSTGRES_PASSWORD=<same-as-DB_PASSWD>
        volumes:
            - pg_data:/var/lib/postgresql/data
        healthcheck:
            test: ["CMD-SHELL", "pg_isready -U romm-user -d romm"]
            interval: 10s
            timeout: 5s
            retries: 5

Extra connection parameters

DB_QUERY_JSON takes a JSON blob of extra parameters appended to the connection string, e.g. for enabling TLS to an external DB, a longer connection timeout, or a non-default port:

environment:
  - DB_QUERY_JSON={"ssl": "true", "connect_timeout": "5"}