{
  config,
  lib,
  ...
}: {
  config = lib.mkIf config.services.paperless.enable {
    assertions = [
      {
        assertion = !config.services.paperless.database.createLocally || config.services.postgresql.enable;
        message = "PostgreSQL must be enabled when using local postgres database for Paperless";
      }
      {
        assertion = !config.services.paperless.database.createLocally || (builtins.any (db: db == "paperless") config.services.postgresql.ensureDatabases);
        message = "Paperless built-in database creation failed - expected 'paperless' in ensureDatabases but got: ${builtins.toString config.services.postgresql.ensureDatabases}";
      }
      {
        assertion = !config.services.paperless.database.createLocally || (builtins.any (user: user.name == "paperless") config.services.postgresql.ensureUsers);
        message = "Paperless built-in user creation failed - expected user 'paperless' in ensureUsers but got: ${builtins.toString (builtins.map (u: u.name) config.services.postgresql.ensureUsers)}";
      }
    ];

    services.paperless.database.createLocally = lib.mkDefault true;

    systemd.services.paperless-scheduler = lib.mkIf config.services.paperless.database.createLocally {
      requires = [
        config.systemd.services.postgresql.name
      ];
    };
  };
}