udpates README and output in compile

README.md

@@ -1 +1,32 @@
 # heroku-buildpack-npmrc
+A Heroku buildpack for overriding the .npmrc file in the build directory with the contents of a config var. Useful for authorizing with npm when installing private packages.
+
+## Configure Multiple Buildpacks
+### _Option 1:_ Heroku CLI or Dashboard
+Add the buildpack to your Heroku app either using the CLI or the Heroku dashboard. The `heroku-buildpack-npmrc` needs to run before any buildpack using npm. In the following example, it runs before the `heroku/nodejs` buildpack.
+```bash
+$ heroku buildpacks:set --index 1 https://github.com/debitoor/heroku-buildpack-npmrc.git
+$ heroku buildpacks:add heroku/nodejs
+```
+
+### _Option 2:_ Use `heroku-buildpack-multi`
+Instead of setting the buildpacks directly with Heroku they can also be configured using a `.buildpacks` in combination with [`heroku-buildpack-multi`]( https://github.com/heroku/heroku-buildpack-multi).
+
+``` bash
+$ heroku buildpacks:set https://github.com/heroku/heroku-buildpack-multi.git  
+```
+
+The same example given for the CLI use would have the following `.buildpacks` file.
+
+``` bash
+$ cat .buildpacks
+https://github.com/debitoor/heroku-buildpack-npmrc.git
+https://github.com/heroku/heroku-buildpack-nodejs.git
+```
+
+## Configure Config Var
+Add the NPMRC config var in Heroku with the contents of your .npmrc file.
+
+``` bash
+ $ heroku config:set NPMRC=//registry.npmjs.org/:_authToken=00000000-0000-0000-0000-000000000000
+```

bin/compile

@@ -5,9 +5,7 @@ build_dir=${1:-}
 npmrc="$(cat $ENV_DIR/NPMRC)"
 
 if [ "$npmrc" != "" ]; then
-	echo "-----> Using NPMRC"
+	echo "-----> Using .npmrc from config var NPMRC"
 	echo "$npmrc" > "$build_dir/.npmrc"
 	exit 0
-else
-	echo "-----> No NPMRC"
 fi