diff --git a/pkgs/development/haskell-modules/configuration-ghc-7.6.x.nix b/pkgs/development/haskell-modules/configuration-ghc-7.6.x.nix
index 0100aade358..50f9585f505 100644
--- a/pkgs/development/haskell-modules/configuration-ghc-7.6.x.nix
+++ b/pkgs/development/haskell-modules/configuration-ghc-7.6.x.nix
@@ -33,12 +33,11 @@ self: super: {
   time = null;
   unix = null;
 
-  # transformers is not a core library for this compiler.
-  transformers = self.transformers_0_4_3_0;
-
-  # haskeline and terminfo are not core libraries for this compiler.
+  # These packages are core libraries in GHC 7.10.x, but not here.
   haskeline = self.haskeline_0_7_2_1;
   terminfo = self.terminfo_0_4_0_1;
+  transformers = self.transformers_0_4_3_0;
+  xhtml = self.xhtml_3000_2_1;
 
   # https://github.com/haskell/cabal/issues/2322
   Cabal_1_22_3_0 = super.Cabal_1_22_3_0.override { binary = self.binary_0_7_4_0; };