net-im/
yowsup

A library that enables you to build applications which use the WhatsApp service

https://github.com/tgalal/yowsup

There are no pull requests

You think something is missing here?
Start with filling a new pull requests.

If you also like to help the Gentoo project, you can consider sending a Pull Request via GitHub.
Before doing so, you might want to take a look at the wiki page.