diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 23ca92d1a..f7effac10 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -42,6 +42,7 @@ node modules:
         - .npm
         - node_modules
   script:
+    - "nix-shell --version"
     - "nix-shell --command 'make node_modules'"
   before_script: &nix-before
     - git config --global init.defaultBranch master
diff --git a/shell.nix b/shell.nix
index 3598f9094..9dfa3e3f9 100644
--- a/shell.nix
+++ b/shell.nix
@@ -275,7 +275,7 @@ in pkgs.mkShell {
   '';
   nativeBuildInputs = [develop inDevelop killallUni2work diffRunning]
   ++ (with pkgs;
-    [ stack nodejs_21 postgresql_12 openldap exiftool expat memcached minio minio-client
+    [ (builtins.trace (lib.version) stack) (builtins.trace (lib.version) nodejs_21) postgresql_12 openldap exiftool expat memcached minio minio-client
       gnumake gup reuse pre-commit
       # busybox # for print services, but interferes with build commands in develop-shell
       htop