Testers are always welcome. If you keep using our alpha (currently 8.90.x) you are already testing.
We really need supporters. As we grow we need people to answer questions and posts in our forum. It doesn’t matter if you are a pro or if you just know the basics in CoreELEC. Community is what we need where everyone helps each other.
Developers are always needed. Especially if you are interested in currently unsupported devices or projects. We are open to new hardware support.
And we need all kinds of people. From the basic idea in a feature request to graphic mock-ups for features or to create community policies, code of conduct, legal advice etc.
I guess everyone can bring something to the table.