diff --git a/pkgs/development/interpreters/spidermonkey/185-1.0.0.nix b/pkgs/development/interpreters/spidermonkey/185-1.0.0.nix
new file mode 100644
index 000000000000..55e0dada71e0
--- /dev/null
+++ b/pkgs/development/interpreters/spidermonkey/185-1.0.0.nix
@@ -0,0 +1,29 @@
+{ stdenv, fetchurl, autoconf213, nspr, perl, python, readline, zip }:
+
+stdenv.mkDerivation rec {
+  version = "185-1.0.0";
+  name = "spidermonkey-${version}";
+
+  src = fetchurl {
+    url = "http://ftp.mozilla.org/pub/mozilla.org/js/js${version}.tar.gz";
+    sha256 = "5d12f7e1f5b4a99436685d97b9b7b75f094d33580227aa998c406bbae6f2a687";
+  };
+
+  buildInputs = [ autoconf213 nspr perl python readline zip ];
+
+  postUnpack = "sourceRoot=\${sourceRoot}/js/src";
+
+  preConfigure = ''
+    export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -I${nspr}/include/nspr"
+    export LIBXUL_DIST=$out
+    autoconf
+  '';
+
+  meta = with stdenv.lib; {
+      description = "Mozilla's JavaScript engine written in C/C++";
+      homepage = https://developer.mozilla.org/en/SpiderMonkey;
+      # TODO: MPL/GPL/LGPL tri-license.
+      maintainers = [ maintainers.goibhniu ];
+  };
+
+}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index fe2fd4a77a97..f68baa73cc64 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2708,6 +2708,7 @@ let
 
   spidermonkey = callPackage ../development/interpreters/spidermonkey { };
   spidermonkey_1_8_0rc1 = callPackage ../development/interpreters/spidermonkey/1.8.0-rc1.nix { };
+  spidermonkey_185 = callPackage ../development/interpreters/spidermonkey/185-1.0.0.nix { };
 
   sysPerl = callPackage ../development/interpreters/sys-perl { };