Long-horizon software engineering on real codebases.
113 original software engineering tasks spanning 91 repositories and 5 languages. Each task requires large, novel fixes not sourced from existing public commits.
Model
Score
Opus 5.5Max
72.3%
GPT-6.1 SolMax
GPT-6 AstraMax
72.0%
DeepSeek-V4.1-FlashMax
71.7%
Opus 5Max
71.4%
Opus 5xHigh
70.2%
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