105 Hidden Bugs Benchmark: DeepSeek V4.1 Flash Scores 24 at $1.80 vs Opus 5's $51

sanderjson · x · 2026-09-10

PawelHuryn ran a real-world benchmark across 2 repos with 105 hidden bugs, asking models to find and fix them:

Takeaway: DeepSeek V4.1 Flash is remarkably strong for everyday coding tasks — nearly matching frontier models at roughly 1/28th the cost of Opus 5.

Related event: DeepSeek V4.1 Flash matches frontier models at 1/100–1/30 the cost in independent tests(9 posts)→

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