how should maintainer make money?

Personally I'd be fine with a commercial license with source available here... the issue isn't the price, it's the fact that you're asked to MITM every network connection you make under the control of a binary blob.

I think it's fair to ask that a developer choosing to build a thing that requires that kind of access should be expected to err on the side of transparency.

You mean “how can I donate?”

https://github.com/evilsocket/opensnitch?tab=readme-ov-file#...

Hunt, gather.