diff --git a/flake.nix b/flake.nix
index fea9890..b958bd9 100644
--- a/flake.nix
+++ b/flake.nix
@@ -100,6 +100,12 @@
                     example = default;
                     description = "Database host";
                   };
+                  port = mkOption rec {
+                    type = types.int;
+                    default = 5432;
+                    example = default;
+                    description = "Database port";
+                  };
                 };
 
                 enableServer = mkOption rec {
@@ -194,7 +200,7 @@
                       if cfg.phx.database.passwordFile != null
                       then ''
                         export DB_PASSWORD=$(cat ${cfg.phx.database.passwordFile})
-                        export DATABASE_URL="ecto://${cfg.phx.database.user}:$DB_PASSWORD@${cfg.phx.database.host}/${cfg.phx.database.name}"
+                        export DATABASE_URL="ecto://${cfg.phx.database.user}:$DB_PASSWORD@${cfg.phx.database.host}:${toString cfg.phx.database.port}/${cfg.phx.database.name}"
                       ''
                       else ''
                         export DATABASE_URL="ecto://${cfg.phx.database.user}@${cfg.phx.database.host}/${cfg.phx.database.name}"