Are you sure that using python is a good idea?

I'm not talking performance here. I mean the maintainability. I've worked on a 50+KLOC python project and maintaining a bigger python codebase is a nightmare.

Python linters suck. Pylint is unable to properly handle classmethods, mypy had some problems too (I don't remember what kind of). The rest of linters will only scream at your style. Unless you have a giant test suite, with a really, really big test coverage and have a CI checking it all at every commit, the project will be unmaintainable. And even with this whole infra, it's a nightmare.

I'm not a fan of C++ either (Rust FTW) but when using a statically-typed language, the compiler at least pays attention that you're not doing utter nonsense.

/edit: btw. I see gajim spewing errors from time to time because the types don't match :P

besides, if shmoose were to be integrated into transponder (not discussed this yet with the main dev) - we're using swiften, so using python here would rule out the possibility of integration