diff --git a/spec/library/postgresql.nix b/spec/library/postgresql.nix
new file mode 100644
index 00000000..dc082ee9
--- /dev/null
+++ b/spec/library/postgresql.nix
@@ -0,0 +1,10 @@
+{ pkgs
+, config
+, ...}: {
+  services.postgresql = {
+    enable = true;
+    dataDir = "/nix/persist/service/postgresql/${config.services.postgresql.package.psqlSchema}";
+
+    package = pkgs.postgresql_15;
+  };
+}