Gulp: Failed to load external module coffee-script/register

For anyone coming across an issue with the

Failed to load external module coffee-script/register

issue, check if you indeed have coffee-script installed:

$ npm ls coffee-script
your-app@1.0.0
└── coffee-script@1.9.0

If you have it installed, delete the node_modules folder, and rerun your install:

$ rm -rf node_modules && npm install