lemmy/docs/src/administration_configuration.md

Configuration

The configuration is based on the file defaults.hjson. This file also contains documentation for all the available options. To override the defaults, you can copy the options you want to change into your local config.hjson file.

To use a different config.hjson location than the current directory, set the environment variable LEMMY_CONFIG_LOCATION. Make sure you copy the defaults.hjson if you do this, otherwise you will be missing settings.

Additionally, you can override any config files with environment variables. These have the same name as the config options, and are prefixed with LEMMY_. For example, you can override the database.password with LEMMY_DATABASE__POOL_SIZE=10.

An additional option LEMMY_DATABASE_URL is available, which can be used with a PostgreSQL connection string like postgres://lemmy:password@lemmy_db:5432/lemmy, passing all connection details at once.

If the Docker container is not used, manually create the database specified above by running the following commands:

cd server
./db-init.sh