Jeff: Jev-compatible 0.8B decision models
The gist
Firelex released Jeff, home-trained 0.8B/2B decision models compatible with Jev's API.
It targets fast, calibrated option-picking rather than reasoning, and is Apache 2.0.
How it unfolded
- Sep 28, 2026Firelex published Jeff, a trio of small decision models fine-tuned from Qwen3.5 and Gemma 4; the linked repo firelex/jeff was created the same day.
- Sep 28, 2026Jeff hit the Hacker News front page as "Jeff – Jev-compatible 0.8B decision models, trained at home, ~30 ms"; the thread had 18 points and 4 comments at the time of the post.
- Sep 28, 2026The same day Supersonic Labs open-weighted the 144M Julia-1 decision model.