[rickdeveloper]

The author did an AMA on Reddit 9 months ago that I think is relevant here: https://old.reddit.com/r/chess/comments/mpasyl/i_started_lic...

In particular:

How they remain free: https://www.reddit.com/r/chess/comments/mpasyl/i_started_lic...

On his salary: https://www.reddit.com/r/chess/comments/mpasyl/i_started_lic...