Use WhatsApp via Your IRC Client with BitlBee
NOTE 2016-09-21: It seems whatsapp-purple has been abandoned by its maintainer. So the things in this guide may stop working over time, and your mileage may vary. This guide is left here for posterity.
Perceptive readers may know that I use a Jolla as my phone. This places quite a few restrictions on what programs can be used on it. For WhatsApp I used to use a native application called Mitäkuuluu by coderus. Unfortunately at some point the program was discontinued, the official Android® version did not run well on the phone and the whole thing was a hassle. So I searched for an alternative way of using WhatsApp, since it has some people I would have trouble contacting otherwise. Since my IRC client is always running (on my server) and is something I check often, I looked into what BitlBee had to offer. I got a setup working and decided to document it for others.