Stealth model Union Alpha scores 74% on DeepSWE, beating GPT-5.6 Sol at lower cost
ZeroStateReflex · x · 2026-09-17
A new stealth model, Union Alpha, has launched and scored 74% on DeepSWE, beating GPT-5.6 Sol and most other models. It reportedly also outperforms GPT-5.6 Sol on Terminal-Bench 2.1 and SWE-Bench Verified while being significantly cheaper. The retweeter speculates it comes from another Chinese lab. The model is available now in any harness via --model=stealth/union-alpha.
Related event: Mystery Model Union Alpha Tops DeepSWE Leaderboard(3 posts)→
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