diff --git a/pkgs/top-level/haskell-defaults.nix b/pkgs/top-level/haskell-defaults.nix
index fb82245344c..f566270d3df 100644
--- a/pkgs/top-level/haskell-defaults.nix
+++ b/pkgs/top-level/haskell-defaults.nix
@@ -17,6 +17,7 @@
 
   ghcHEADPrefs =
     self : self.haskellPlatformArgs_future self // {
+      haskellPlatform = null;
       binary = null; # now a core package
     };