Coding agents craft arbitrary code so securing them is more complicated than red-teaming. We post trained a cyber-security small llm, changed how it reasons and supplemented our controls using program analysis techniques such as inline reference monitoring to outperform GPT5.5-xhigh on hard benchmarks like LinuxArena and SleightBench.
Free product available at harden.run and full benchmarks in the blog post.
Show HN: Beating GPT5.5-xhigh for Coding agent security with SLMs and IRM
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