I'm running Node.js 0.10.21. I tried both CoffeeScript 1.6.3 and master both with and without require('coffee-script/extensions'). Compiling the two files to JavaScript and running them directly in Node works just fine of course. # ./folder/a.coffee require('../b').test() # ./b.coffee exports.test = -> console.log 'yay' # $ coffee folder/a.coffee # # Error: Cannot find module '../b' # at Function.Module._resolveFilename (module.js:338:15) # at Function.Module._load (module.js:280:25) # at Module.require (module.js:364:17) # at require (module.js:380:17) # at Object.<anonymous> (/Users/test/folder/a.coffee:1:1) # at Module._compile (module.js:456:26)