Yeah, Ninji's work on reverse engineering CoDi has been excellent for my Rust work. Very useful
With codi-app, that's also helped me to expose a standardised D-Bus interface.. that way, it can run on Sailfish/UBPorts/Gemian.
The thing about codi-app for me, is that it feels rather hacked together. I don't know if its merely an initial version.. but I don't know. Just doesn't seem polished as I'd imagine..