MirrorCode, released by @EpochAIResearch on X/Twitter on 2026-06-26, is a long‑horizon SWE benchmark designed to let AI code autonomously for days. The team says top models can finish certain projects they estimate would take human engineers several weeks; the post includes a video demonstrating multi‑day autonomous development.
MirrorCode is a long‑horizon software engineering benchmark created by @EpochAIResearch (posted on X/Twitter on 2026-06-26) that lets AI systems run autonomously for days to perform coding tasks.
What are the largest software engineering tasks AI can perform?
To answer this, we built MirrorCode, our long-horizon SWE benchmark that lets AI code autonomously for days at a time.
The best models complete some tasks we estimate would take human engineers several weeks.
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