> it's like one Claude prompt to add MIPS support to this

Can you provide the code somewhere? Is it complete? Does it really work? I have a hard time to believe that an LLM really can generate a complete and working backend for a target architecture with "one prompt". From my experience with such tools, by the end of the day it takes longer until it covers all edge cases and actually works than when writing it myself.

They absolutely can for simpler cases like this, especially recent GPT 5.x models are amazing at such lower-level compiler work.