diff --git a/pkgs/development/haskell-modules/configuration-ghc-7.10.x.nix b/pkgs/development/haskell-modules/configuration-ghc-7.10.x.nix
index 5a844d7269dc..2135dee4b0ee 100644
--- a/pkgs/development/haskell-modules/configuration-ghc-7.10.x.nix
+++ b/pkgs/development/haskell-modules/configuration-ghc-7.10.x.nix
@@ -139,11 +139,10 @@ self: super: {
     url = "https://github.com/fpco/conduit-combinators/pull/16.patch";
     sha256 = "0jpwpi3shdn5rms3lcr4srajbhhfp5dbwy7pl23c9kmlil3d9mk3";
   });
-  yesod-bin = overrideCabal (appendPatch super.yesod-bin (pkgs.fetchpatch {
+  yesod-bin = appendPatch super.yesod-bin (pkgs.fetchpatch {
     url = "https://github.com/yesodweb/yesod/pull/966.patch";
-    sha256 = "0jxhj3ls0xsw81mmiiy3ln1yb910r6p87vkqpaw8xdczly4h98fc";
-  })) (drv: {
-    patchFlags = "-p2";
+    sha256 = "0mm4swyn7qh30hw7ya8ykz5qvsd4ni4vmipq364yqbsi9ysrc6nb";
+    stripLen = 1;
   });
 
   ghcjs-prim = self.callPackage ({ mkDerivation, fetchgit, primitive }: mkDerivation {