Open Source Contributions Accepted?

Forgive me if I am mistaken, but it does not look like the actual Anytype application is publicly available in GitHub. If developers such as myself wish to contribute, is there an application procedure or process that needs to be completed to contribute? It is pretty rare to find projects that align so closely with some of my values on privacy and knowledge exchange, and I would love to help out if I can!

Go to https://anytype.io/ and scroll aaaaaaaaaaaaalll the way to the bottom. There you will find this button: