Jev AI vs Open Source: Can GLiNER Replace It?
Jev is one of the most hyped AI models of the year, and it isn't an LLM. TypeSafe's "System One" model doesn't generate text. It makes typed, calibrated decisions in ~90ms. In this video we cover what Jev is and how its API works. We look at why calibrated probability is the real unlock, where Jev fits next to LLMs (and where it doesn't), and the open-source "OpenJev" alternatives you can run on your own machine. Finally, we think fast and slow, pairing a System One model with an LLM coach to beat solo Jev at Doom. 📌 Full article with benchmarks, charts and methodology: https://jamesbriggs.io/understanding-jev What we found: - Calibration: Jev's confidence means something. ECE 0.053 vs 0.119 for gpt-5.6-luna on CLINC150. - Speed: ~90ms per call on the server vs ~700ms for gpt-5.6-luna with no reasoning. Extra questions in the same call add no latency. - Accuracy: Jev matches or beats gpt-5.6-luna on 5 of 6 intent, tool-selection and guardrail benchmarks. - Open source: GLiNER2.5 and GLiGuard run in 10–50ms on an M4 Pro Mac and come close on several benchmarks. They don't match Jev's calibration yet. - Fast + slow: adding an LLM coach to Jev and GLiNER gives ~4x their solo Doom deathmatch scores. ⏱️ Chapters 0:00 Intro 1:22 What is JEV? 2:40 Inputs and outputs 4:26 Three types of decision 6:35 Calibrated probability 10:38 Ultra-fast 11:44 Where JEV fits 14:58 Closed source 16:39 Open-source alternatives 20:28 GLiNER 23:33 The trade-offs 25:42 Thinking fast and slow 31:30 What to make of JEV 👋 Find me X: https://x.com/jamescalam LinkedIn: https://www.linkedin.com/in/jamescalam/ GitHub: https://github.com/jamescalam #AI #LLM #AIAgents