> and it really is the best tool for terminal graphics in my opinion

Not sixel or kitty graphics?

One of the really cool things about chafa is that it has both sixel and kitty graphic renderers! (and iterm2 images as well) So you can output kitty if the terminal supports it, but fall back to ascii if it doesn’t.

What interests me about it is the unicode mosaic output format that looks higher quality than the usual upper half block or braille character approaches without needing to support a special protocol.

Setting aside the usual compatibility issues with those things.. neither are available from your buildbot. Also while Jupyter does supports images other notebooking ecosystems may not, and anyway you need a file whereas chafa can work with streams.