diff --git a/shells/dodona.nix b/shells/dodona.nix
index b1359ad1..a9862ea1 100644
--- a/shells/dodona.nix
+++ b/shells/dodona.nix
@@ -61,6 +61,6 @@ pkgs.devshell.mkShell {
   };
   language.ruby = {
     package = pkgs.ruby_3_1;
-    nativeDeps = [ pkgs.libmysqlclient pkgs.zlib pkgs.libffi ];
+    nativeDeps = [ pkgs.libmysqlclient pkgs.zlib pkgs.libffi pkgs.libyaml ];
   };
 }