Added support to for OS X to the Electron package.

For OS X:

  1. I download and extract Electron.app
  2. put it in `$out/Applications`
  3. link the binary to `$out/bin/electron`

pkgs/development/tools/electron/default.nix

@@ -1,8 +1,19 @@
 { stdenv, lib, libXScrnSaver, makeWrapper, fetchurl, unzip, atomEnv }:
 
-stdenv.mkDerivation rec {
-  name = "electron-${version}";
+let
   version = "1.2.2";
+  name = "electron-${version}";
+
+  meta = with stdenv.lib; {
+    description = "Cross platform desktop application shell";
+    homepage = https://github.com/electron/electron;
+    license = licenses.mit;
+    maintainers = [ maintainers.travisbhartwell ];
+    platforms = [ "x86_64-darwin" "x86_64-linux" ];
+  };
+
+  linux = {
+    inherit name version meta;
 
     src = fetchurl {
       url = "https://github.com/electron/electron/releases/download/v${version}/electron-v${version}-linux-x64.zip";
@@ -27,12 +38,27 @@ stdenv.mkDerivation rec {
       wrapProgram $out/lib/electron/electron \
         --prefix LD_PRELOAD : ${stdenv.lib.makeLibraryPath [ libXScrnSaver ]}/libXss.so.1
     '';
-
-  meta = with stdenv.lib; {
-    description = "Cross platform desktop application shell";
-    homepage = https://github.com/electron/electron;
-    license = licenses.mit;
-    maintainers = [ maintainers.travisbhartwell ];
-    platforms = [ "x86_64-linux" ];
   };
-}
+
+  darwin = {
+    inherit name version meta;
+
+    src = fetchurl {
+      url = "https://github.com/electron/electron/releases/download/v${version}/electron-v${version}-darwin-x64.zip";
+      sha256 = "0rqlpj3400qjsfj8k4lwajrwv5l6f8mhrpvsma7p36fw5qjbwp1z";
+      name = "${name}.zip";
+    };
+
+    buildInputs = [ unzip ];
+
+    buildCommand = ''
+    mkdir -p $out/Applications
+    unzip $src
+    mv Electron.app $out/Applications
+    mkdir -p $out/bin
+    ln -s $out/Applications/Electron.app/Contents/MacOs/Electron $out/bin/electron
+    '';
+  };
+in
+
+  stdenv.mkDerivation (if stdenv.isDarwin then darwin else linux)