diff --git a/packages/nixmacs/default.nix b/packages/nixmacs/default.nix
index 4c15a2c..a2c00f9 100644
--- a/packages/nixmacs/default.nix
+++ b/packages/nixmacs/default.nix
@@ -103,6 +103,7 @@
 	gcc # for C++ code blocks
 	python3 #for python code blocks
         #kdePackages.qtdeclarative #qmlls
+	swi-prolog
       ]);
 
     # Optionally override derivations.