I really love firmware for this reason. Each instruction you send to the CPU means something. If you want, you can rip back all the abstraction and just run raw

I really love firmware for this reason. Each instruction you send to the CPU means something. If you want, you can rip back all the abstraction and just run raw assembly. Sometimes the compiler can be very wrong and you get to embed the correct assembly in your C and suddenly the program is 10x faster. True story! Trying to fit my application in 1kB of flash and one hundred twenty-eight entire bytes of RAM taught me a lot as a young programmer. It really makes you confront the physicality of the machine your code represents. I don't think nearly enough programmers have that experience