diff --git a/pkgs/development/haskell-modules/non-hackage-packages.nix b/pkgs/development/haskell-modules/non-hackage-packages.nix
index 6b8477b524bf..68fcbdb79a5d 100644
--- a/pkgs/development/haskell-modules/non-hackage-packages.nix
+++ b/pkgs/development/haskell-modules/non-hackage-packages.nix
@@ -10,7 +10,9 @@ self: super: {
   multi-ghc-travis = throw ("haskellPackages.multi-ghc-travis has been renamed"
     + "to haskell-ci, which is now on hackage");
 
+  # https://github.com/channable/vaultenv/issues/1
   vaultenv = self.callPackage ../tools/haskell/vaultenv { };
 
+  # https://github.com/diku-dk/futhark/issues/614
   futhark = self.callPackage ../compilers/futhark { };
 }