Fighter planes in the 1950s used the Bendix Central Air Data Computer to determine air speed, mach number, altitude and so forth from pressure. It is electromechanical, using gears and synchros for its computations. Amazingly, it is modular and can be easily disassembled.
We separated the top layer from the rest for testing. The "interface" between the layers is two gears and an electrical connection. The electronic servo amplifier blocks come off too.
(3 photos in link)
The whole software is currently considered alpha. If you want to test bleeding edge stuff, you could build the main branch locally and test that. Or you could use the app releases and report bugs on github (the devs would much prefer pull requests fixing bugs than just reports and they're great at merging). I'm not a dev but I have contributed to the app.