Hi, the author of Gea here. Gea is built upon the principles introduced by 11 years of history, based on all of the UI frameworks I have authored so far, the most recent of which are erste and regie from 2017-2019. And Gea itself is written over 6 months, the history of which is compressed in the initial commit as I don't believe in populating Github history with crappy commits that alter design decisions and introduce breaking changes. You can imagine Gea was closed source before the 1.0.0 launch, and made only open at the end.