Could you share what are the most complex engineering parts that you should deal with? Could you share your engineering documents even if they are just WIP?

Personally I am interested in how engines like Blitz, Servo, et al could be built in the future using formal methods practices. For example, start with definitions and generate part of the system. Nowadays, this includes LLM but I see them more like great tools than AI systems. Also things like Z3 comes to my mind.

BTW, some of my companies has a research branch on things like this.