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The win came from the harness, not a bigger model

What's this about?

HN commenters read AISLE's homepage and repository and worked out the method. It is AI-guided fuzzing built on libFuzzer or AFL: have the LLM identify interesting functions to test, have it generate the fuzzing harnesses, then have it triage the fuzzer's findings at a high level. And one commenter found the scanner's default model in the code: gpt-5.4-nano — not a frontier model, and not even a large one.

Why does that change the story?

Because the headline reads as "a small company's AI beat OpenAI's and Anthropic's", and the mechanism is different: a cheap model wrapped in a good harness beat two frontier models wrapped in whatever Codex Security and Mythos use. Fuzzing is a proven technique that generates *executable evidence* — a crashing input, not a claim — which is why the findings survived expert review. The model's job was to point the fuzzer somewhere useful and sort the results, and a nano model can do that.

Why does this matter to you?

  1. It is the strongest empirical case this month for the argument three separate papers have made: the harness dominates the model.
  2. It arrives the same day as FrontierHarness measuring a 17× cost spread across harnesses running the identical model.
  3. The practical read for security tooling: pairing an LLM with a deterministic tool that produces verifiable artifacts beats asking a bigger model to reason about code.
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