We released Filmbox two years ago, and it has gotten a great response. It's been used in huge movies like "Everything Everywhere All At Once".
It's been a huge rewrite to get this working on Linux and Windows from our original Mac and Metal code.
We also have some interesting uses of cross-platform Swift + Electron in our plugin manager app, and cross-platform Swift generally in the plugin. Hopefully we can detail that in a blog post at some point.
There's a free Filmbox Lite version to try, if you're interested.
Maybe show the buildup of layers? That would be really interesting.