diff --git a/pkgs/development/libraries/vapoursynth/default.nix b/pkgs/development/libraries/vapoursynth/default.nix
index b78db1673168..6abc58494da6 100644
--- a/pkgs/development/libraries/vapoursynth/default.nix
+++ b/pkgs/development/libraries/vapoursynth/default.nix
@@ -4,8 +4,6 @@
 , ApplicationServices
 }:
 
-with lib;
-
 stdenv.mkDerivation rec {
   pname = "vapoursynth";
   version = "R58";
@@ -25,7 +23,7 @@ stdenv.mkDerivation rec {
   buildInputs = [
     zimg libass
     (python3.withPackages (ps: with ps; [ sphinx cython ]))
-  ] ++ optionals stdenv.isDarwin [ libiconv ApplicationServices ];
+  ] ++ lib.optionals stdenv.isDarwin [ libiconv ApplicationServices ];
 
   enableParallelBuilding = true;
 
@@ -58,5 +56,4 @@ stdenv.mkDerivation rec {
     platforms   = platforms.x86_64;
     maintainers = with maintainers; [ rnhmjoj sbruder tadeokondrak ];
   };
-
 }