Add empty node-packages.nix using build-node-package.nix from npm2nix.

buildNodePackage is a function to build npm packages.

npm2nix (https://bitbucket.org/shlevy/npm2nix) can be used to generate subexpressions to go in node-packages.nix

pkgs/development/web/nodejs/build-node-package.nix

@@ -0,0 +1,35 @@
+{ stdenv, nodejs }:
+
+args @ { src, deps, ... }:
+
+stdenv.mkDerivation ({
+  unpackPhase = "true";
+
+  configurePhase = ''
+    runHook preConfigure
+    mkdir node_modules
+    ${stdenv.lib.concatStrings (map (dep: ''
+      ln -sv ${dep}/node_modules/${(builtins.parseDrvName dep.name).name} node_modules/
+    '') deps)}
+    export HOME=$(pwd)
+    runHook postConfigure
+  '';
+
+  buildPhase = ''
+    runHook preBuild
+    ${nodejs}/bin/npm --registry http://www.example.com install ${src}    
+    runHook postBuild
+  '';
+
+  installPhase = ''
+    runHook preInstall
+    mkdir $out
+    mv node_modules $out
+    if [ -d "$out/node_modules/.bin" ]; then
+      ln -sv node_modules/.bin $out/bin
+      find -L $out/node_modules/.bin/* -type f -print0 | \
+        xargs -0 sed --follow-symlinks -i 's@#!/usr/bin/env node@#!${nodejs}/bin/node@'
+    fi
+    runHook postInstall
+  '';
+} // args)

pkgs/top-level/node-packages.nix

@@ -0,0 +1,12 @@
+{ pkgs, stdenv, nodejs }:
+
+let buildNodePackage = import ../development/web/nodejs/build-node-package.nix {
+  inherit stdenv nodejs;
+}; in
+
+with pkgs;
+
+let self = {
+};
+
+in self