diff --git a/example/simple/flake.nix b/example/simple/flake.nix
index 7e4957a..04fcdb3 100644
--- a/example/simple/flake.nix
+++ b/example/simple/flake.nix
@@ -45,7 +45,7 @@
                 pgcfg = config.services.postgres.pg1;
               in
               {
-                environment.PGWEB_DATABASE_URL = "postgres://$USER@${pgcfg.listen_addresses}:${builtins.toString pgcfg.port}/${dbName}";
+                environment.PGWEB_DATABASE_URL = pgcfg.connectionURI dbName;
                 command = pkgs.pgweb;
                 depends_on."pg1".condition = "process_healthy";
               };
diff --git a/nix/postgres/default.nix b/nix/postgres/default.nix
index 0d48078..5ce96c2 100644
--- a/nix/postgres/default.nix
+++ b/nix/postgres/default.nix
@@ -56,6 +56,14 @@ in
       description = "The DB socket directory";
     };
 
+    # Based on: https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING-URIS
+    connectionURI = lib.mkOption {
+      type = lib.types.functionTo lib.types.str;
+      readOnly = true;
+      default = dbName: "postgres://${config.listen_addresses}:${builtins.toString config.port}/${dbName}";
+      description = "A function that accepts database name and returns the [postgres connection URI](https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING-URIS)";
+    };
+
     hbaConf =
       let
         hbaConfSubmodule = lib.types.submodule {