Summary & Key Takeaways ​

• Drew Breunig embedded a working NES 6502 CPU emulator into Qwen3.5-4B's weights.
• This allows playing NES ROMs, such as Super Mario Bros, directly within the LLM.
• The project was inspired by Divyansh Agrawal's qwenputer.
• Opus 5.5 prompts were used to guide the model's development.
• The emulator uses conformance tests for the NES CPU released 15 years ago.

Our Commentary ​

Okay, this is absolutely wild. An NES emulator inside an LLM? My brain is genuinely struggling to process the implications. It's not just a cool hack; it's a profound demonstration of emergent computation and the unexpected capabilities of these models. We're moving beyond just text generation into something far more complex. I don't even know how to feel about it, but it's definitely pushing the boundaries of what I thought was possible.