Don't use, it has been modified to adapt to a specific use-case and probably wont work for you.

forked from https://github.com/keslar/yourls-multi-user which is a modification of the multi-user 1.7 beta yourls plugin created by Matheus (X-warrior) Bratfisch.  The original can be found: http://www.matbra.com/en/code/multi-user-yourls-plugin/