github-username-regex-js/module.js

A regular expression that only matches a valid GitHub or GitHub EMU username

export default /^(?:[a-z\d](?:[a-z\d]|-(?=[a-z\d])){0,38}|[a-zA-Z0-9]+(-[a-zA-Z0-9]+)*(_[a-zA-Z0-9]+))$/i;