News/Research
Worth readingResearch·NoiseSingle source· treat as leadstableUpdated Oct 30·Updated 1×·First seen Nov 3
NESformer: Drew Breunig Implements a Deterministic NES Emulator Within Qwen 3.5-4B Weights
Open sourcePractical
Read up
Context that changes how you build, even if there's nothing to install.
On October 30, 2026, Drew Breunig released NESformer, a project that implements a functional NES 6502 CPU emulator within the weights of a Qwen 3.5-4B model, allowing the model to run NES ROMs.
It demonstrates that neural networks can function as non-traditional computational substrates for deterministic binary logic.
AILookup take
An incredibly clever hack, but effectively useless for real-world AI building. It’s a fascinating proof of concept for neural computation that will have no impact on your daily workflow.
Who cares
retro computing hobbyistsLLM researchers
Watch next
Someone running a more complex architecture, like a RISC-V processor, inside a larger model's weights.
Also covers
- NESformer: Qwen 3.5-4B Implemented As a Deterministic NES EmulatorDeveloper Drew Breunig released 'NESformer,' which implements a working 6502 CPU (the core of the NES) directly within the weights of Qwen 3.5-4B. The model functions as a deterministic emulator for Nintendo hardware.
Details
- Demonstrates the ability of neural networks to function as non-traditional computational substrates.
- Proves that LLMs can store and execute complex, deterministic binary logic within their architecture.
- Highlights an unconventional alternative to traditional code execution or FPGA-based emulation.
Related articles (3)
dbreunig/nesformerSimon WillisonHacker News· 3 stories
More in Research
GitHub Octoverse 2026 Report Reveals Record Platform Activity and Surge in AI Agent Growth1 source · Oct 28OpenAI Research Claims Frontier Models Refuted Exponential Time Hypothesis3 sources · Oct 27Google DeepMind Launches Genie 4 As Interactive World Model with Audio5 sources · Oct 27OpenAI Stops Training Frontier Models on Live Internet Data2 sources · Oct 23Developments in AI Agent Infrastructure and Integration11 sources · Oct 23