Configuration reference

Set values in the repository's .env before starting Compose. This is a focused overview; the environment template contains the complete set.

Setting	Purpose
SURLS_IMAGE	Pin a published Surls release image for predictable updates.
POSTGRES_PASSWORD	Database password used by the Compose PostgreSQL service. Generate a hex value.
AUTH_SECRET	Authentication and encrypted-credential key. Keep stable and back it up.
NEXT_SERVER_ACTIONS_ENCRYPTION_KEY	Stable key shared by build and runtime for Server Actions.
BASE_URL	Exact public Surls application origin, without trailing slash.
WEBAUTHN_RP_ID, WEBAUTHN_ORIGIN	Passkey hostname and matching origin.
SURLS_PORT	Published app port; use 127.0.0.1:3000 for a local reverse proxy.
SURLS_PUBLIC_WEBROOT_PATH	Existing read-only public-page directory, default ./www.
SURLS_UPLOADS_PATH	Existing writable upload directory, default ./uploads.
INITIAL_ADMIN_EMAIL, INITIAL_ADMIN_NAME, INITIAL_ADMIN_PASSWORD	First admin; remove the password after first login.
TRUST_PROXY	Leave false unless you control and sanitize every proxy hop.
TURNSTILE_SITE_KEY, TURNSTILE_SECRET_KEY	Optional pair; set both or neither.
UPLOAD_MAX_BYTES	Lower the 25 MiB request ceiling.
UPLOAD_USER_STORAGE_QUOTA_BYTES, UPLOAD_SITE_STORAGE_QUOTA_BYTES	Upload quota controls.
CLICK_EVENT_RETENTION_DAYS, AUDIT_LOG_RETENTION_DAYS	Retention windows, 365 days by default.

DATABASE_URL in .env is for host-run development. Compose builds the app's container connection URL from POSTGRES_* values and the internal database hostname. Optional SMTP and external-provider settings are listed in the deployment and external sign-in guides.