diff --git a/pkgs/development/libraries/allegro/default.nix b/pkgs/development/libraries/allegro/default.nix
index 15bb6bf1d000..213b086c3ccf 100644
--- a/pkgs/development/libraries/allegro/default.nix
+++ b/pkgs/development/libraries/allegro/default.nix
@@ -41,6 +41,7 @@ rec {
   ];
 
   meta = {
+    branch = "4";
     description = "A game programming library";
     license = "free-noncopyleft"; # giftware
     maintainers = with a.lib.maintainers;