diff --git a/pkgs/development/interpreters/duktape/default.nix b/pkgs/development/interpreters/duktape/default.nix
index c296d013e3d1..8477aef9ca43 100644
--- a/pkgs/development/interpreters/duktape/default.nix
+++ b/pkgs/development/interpreters/duktape/default.nix
@@ -1,10 +1,10 @@
 { lib, stdenv, fetchurl, validatePkgConfig }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "duktape";
   version = "2.7.0";
   src = fetchurl {
-    url = "http://duktape.org/duktape-${version}.tar.xz";
+    url = "http://duktape.org/duktape-${finalAttrs.version}.tar.xz";
     sha256 = "sha256-kPjS+otVZ8aJmDDd7ywD88J5YLEayiIvoXqnrGE8KJA=";
   };
 
@@ -38,4 +38,4 @@ stdenv.mkDerivation rec {
     mainProgram = "duk";
     platforms = platforms.all;
   };
-}
+})