diff --git a/pkgs/applications/audio/sfxr/default.nix b/pkgs/applications/audio/sfxr/default.nix
index 1a35fe8830f4..42a9b2452991 100644
--- a/pkgs/applications/audio/sfxr/default.nix
+++ b/pkgs/applications/audio/sfxr/default.nix
@@ -8,12 +8,12 @@
 , wrapGAppsHook
 }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "sfxr";
   version = "1.2.1";
 
   src = fetchurl {
-    url = "http://www.drpetter.se/files/sfxr-sdl-${version}.tar.gz";
+    url = "http://www.drpetter.se/files/sfxr-sdl-${finalAttrs.version}.tar.gz";
     sha256 = "0dfqgid6wzzyyhc0ha94prxax59wx79hqr25r6if6by9cj4vx4ya";
   };
 
@@ -53,5 +53,4 @@ stdenv.mkDerivation rec {
     maintainers = with maintainers; [ fgaz ];
     platforms = platforms.unix;
   };
-}
-
+})