I don't get mocha to build with browserify, I always get

Error: Cannot find module '../suite' from '/Users/me/tddbin-frontend/node_modules/mocha'

The problems mentioned in thoseissues seem to have no solution provided yet. It seems that browserify picks up a built mocha.js and can't handle some magic done in there.
My solution for now is to use mocha from the CDN, which might not work in all use cases, but does for me now.