Grunt Coffee Server

by Andy Appleton

TL;DR I wrote a Grunt task to live compile CoffeeScript for local development.

Full story

Somewhat inspired by my colleague Phil’s tweet, I’ve written a Grunt plugin to make it easy to start writing any JavaScript project in CoffeeScript.

It’s a simple static web server with a twist – request a .js file and it will be returned if it exists. If it doesn’t exist then the server will try and find a .coffee version of the file and return the compiled output if it can.

N.B. It does not deal with compilation for deployment, there’s already a plugin for that.


This is packaged up as a Grunt task so you’ll need to install Grunt from NPM first (might as well do that globally):

npm install -g grunt

Then install the task:

npm install grunt-coffee-server

Next you’ll need a gruntfile:

grunt init:gruntfile

Follow the instructions and take a look in your new grunt.js file. We need to register the new task by adding the following line:


There are also a couple of configuration options available which are read from the server config key:

  server: {
    port: 1337 // defaults to 3000 if not set
    base: './public' // defaults to ./ if not set

Finally run the server:

grunt coffee-server

I’ve written this kind of server manually a few times now for local development so I know it’ll be handy for me – hopefully it’ll be useful for you too.

It’s on GitHub so feel free to fork, pull request etc!