Signalling and train control systems typically have two independent implementations - full stack: hardware, os, software, different development teams. I guess

Signalling and train control systems typically have two independent implementations - full stack: hardware, os, software, different development teams. I guess you'd need three separate implementations to achive some redundancy when you can't just slam the emergency brakes if the systems disagree. (... For some reason, I find it higly demotivating that another team is doing the exact same thing. Maybe I just want to be a snowflake...)