I’ve built a retro operating system and programming environment for ESP32 microcontrollers called BASIC32.
I took it to 39% complete, as a language, over 8-weeks. Then, I spent just 50 minutes describing all the missing parts and it finished the language in 1-shot. I didn’t think it would work. It did.
I used Opus 5.5 on a $20 plan and I didn’t even hit my limits.
I have a feeling that the 39% served as a good framework for the LLM to work on the remaining part while keeping it consistent with the existing structure and style. So, in a sense, your 8 weeks are a big part of why it succeeded.