diff --git a/configuration.nix b/configuration.nix
index 2d1dedf..b500d83 100644
--- a/configuration.nix
+++ b/configuration.nix
@@ -103,6 +103,7 @@
     cacert
     code-cursor
     adwaita-icon-theme
+    gtk3  # Provides org.gtk.Settings.FileChooser schema for FreeCAD
     pkgs-unstable.claude-code  # Use unstable for latest version
     yubikey-manager
   ];