diff --git a/lib/customisation.nix b/lib/customisation.nix
index 304bb228449f..217daada7818 100644
--- a/lib/customisation.nix
+++ b/lib/customisation.nix
@@ -81,7 +81,7 @@ rec {
         });
       };
 
-  in lib.fixedPoints.makeExtensibleWithInterface (x: o: interface (addOverrideFuncs x o) o) (output: self: {
+  in lib.makeExtensibleWithInterface (x: o: interface (addOverrideFuncs x o) o) (output: self: {
     args = origArgs;
     val = f output self.args self.val;
   });
diff --git a/lib/default.nix b/lib/default.nix
index 3e30ec515fcb..9da78ff0da7c 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -60,7 +60,7 @@ let
       nixpkgsVersion mod;
 
     inherit (fixedPoints) fix fix' extends composeExtensions
-      makeExtensible makeExtensibleWithCustomName;
+      makeExtensible makeExtensibleWithCustomName makeExtensibleWithInterface;
     inherit (attrsets) attrByPath hasAttrByPath setAttrByPath
       getAttrFromPath attrVals attrValues catAttrs filterAttrs
       filterAttrsRecursive foldAttrs collect nameValuePair mapAttrs
@@ -88,7 +88,8 @@ let
     inherit (stringsWithDeps) textClosureList textClosureMap
       noDepEntry fullDepEntry packEntry stringAfter;
     inherit (customisation) overrideDerivation makeOverridable
-      callPackageWith callPackagesWith addPassthru hydraJob makeScope;
+      callPackageWith callPackagesWith addPassthru hydraJob makeScope
+      callPackageWithOutputWith;
     inherit (meta) addMetaAttrs dontDistribute setName updateName
       appendToName mapDerivationAttrset lowPrio lowPrioSet hiPrio
       hiPrioSet;
diff --git a/pkgs/top-level/haskell-packages.nix b/pkgs/top-level/haskell-packages.nix
index dce783b3f98a..a1f9b2e81c3c 100644
--- a/pkgs/top-level/haskell-packages.nix
+++ b/pkgs/top-level/haskell-packages.nix
@@ -24,7 +24,7 @@ let
   };
 
   callPackage = lib.callPackageWith (pkgs // { inherit haskellLib; });
-  callPackageWithOutput = lib.customisation.callPackageWithOutputWith (pkgs // { inherit haskellLib; });
+  callPackageWithOutput = lib.callPackageWithOutputWith (pkgs // { inherit haskellLib; });
 
 in rec {
   lib = haskellLib;
diff --git a/pkgs/top-level/splice.nix b/pkgs/top-level/splice.nix
index 599c108062c0..d6498be949b3 100644
--- a/pkgs/top-level/splice.nix
+++ b/pkgs/top-level/splice.nix
@@ -86,5 +86,5 @@ in
 
   newScope = extra: lib.callPackageWith (splicedPackages // extra);
 
-  newScopeWithOutput = extra: lib.customisation.callPackageWithOutputWith (splicedPackages // extra);
+  newScopeWithOutput = extra: lib.callPackageWithOutputWith (splicedPackages // extra);
 }