Jev AI Model: Full Breakdown & Transcript

An ex-OpenAI researcher just deleted language from the LLM...

0h 05m video Published Sep 21, 2026 Transcribed Sep 21, 2026 Fireship Fireship
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Intermediate 5 min read For: Developers and tech enthusiasts interested in AI and machine learning.
AI Trust Score 70/100
โš ๏ธ Average / Some Fluff

"The title promises a world-changing event, but the video delivers a solid overview with some hype and a sponsor segment. It's informative but not as groundbreaking as the title suggests."

AI Summary

This video from The Code Report covers the release of Jev, a new type of AI model from Typesafe AI that is designed to be fast, cheap, and reliable for classification tasks. Unlike traditional large language models, Jev is a System 1 model that provides calibrated confidence scores and is 200 times faster and 400 times cheaper than its competitors. The video also discusses the controversy surrounding Jev, including claims that it is not original and that it has been reproduced by open-source developers.

[00:00]
Jev's Release

An ex-OpenAI researcher released Jev, a new frontier model after two years in stealth development. It is a System 1 model that is fast and cheap, unlike traditional LLMs.

[00:14]
Jev's Capabilities

Jev cannot talk, write code, or write essays. It is designed for quick, gut-instinct decisions, returning a choice, a score, or null. It has guaranteed schema matching and no hallucinations.

[00:27]
The Problem with LLMs

Large language models have a fatal flaw: they are verbose and expensive. Jev fixes this by deleting language from the model, making it 200 times faster and 400 times cheaper.

[00:56]
Jev's Creator and Company

Jev was created by ex-researcher Diogo Almeida and his company Typesafe AI, which just raised a significant amount of funding. The name reflects its behavior as a typesafe programming language.

[01:45]
How Jev Works

Jev uses a technique called RLCD (Reinforcement Learning for Calibrated Decisions) to provide confidence values with each response. It is a System 1 model, inspired by Daniel Kahneman's work.

[03:04]
Jev's Performance and Controversy

Jev is fast and cheap, but not always correct. It has been criticized for being similar to zero-shot classifiers from the past, and some claim it is not original. Open-source developers have already built alternatives like OpenJev.

[04:14]
Sponsor: Mux

The video is sponsored by Mux, a video API platform that offers hosting, streaming, and AI-powered features like transcription and moderation. It is used by companies like Perplexity and Patreon.

Jev represents a significant shift in AI, offering a fast, cheap, and reliable alternative to traditional LLMs for classification tasks. However, its originality and performance are still debated, and the open-source community has already begun to replicate its capabilities.

Mentioned in this Video

๐Ÿ’ก Key Takeaways

๐Ÿ“Š

Jev's Release

This is the core topic of the video, introducing a new AI model that could change the industry.

๐Ÿ’ก

The Problem with LLMs

Highlights a key pain point for developers, making the video relatable and relevant.

00:27
๐Ÿ”ง

How Jev Works

Explains the technical foundation of Jev, which is crucial for understanding its value proposition.

01:45
๐Ÿ’ก

Jev's Controversy

Adds a critical perspective, showing that Jev is not without its detractors.

03:43

[00:00] Last week, everything about AI changed forever. I realize everything about AI changes forever almost every week, but this time, AI changed forever more than usual. Because one of the open AI researchers behind the instruction-following work that eventually became ChatGPT

[00:14] just released the next big frontier model after two years in stealth development. A model that can't talk, a model that can't write code, a model that can't write your college essays, and a model that will never tell you you're absolutely right. Its name is Jev.

[00:27] My name is Jev. And this is a huge deal because large language models have one fatal flaw, that they won't shut the hell up. You give Fable or Astra a simple instruction, like return true or false, and it'll discover a third option after thinking for 4,000 tokens

[00:41] and then charge your credit card 11 cents. Jev fixed this problem with a radical solution. It deleted language from the large language model, and the result is a new type of classifier that's 200 times faster, 400 times cheaper, with free output tokens and zero hallucinations.

[00:56] Sounds too good to be true, so in today's video, we'll take a look at Jev's code, it's Trust Me Bro Benchmarks, and the dude who says he built an open source Jev over a year ago. It is September 21st, 2026, and you're watching The Code Report.

[01:08] The big AI duopoly is literally shaking right now because Jev is a cheaper, faster way to solve basically any AI problem that requires a quick gut instinct decision It afraid But the first thing you need to know is that Jev was created by an ex researcher Diogo Almeida and his company Typesafe AI which just raised million

[01:30] But the company name is the first clue to what Jev really is. Like a regular large language model, you send it a question and some context, like a bunch of unstructured text. However, it differs because it behaves more like a Typesafe programming language, like TypeScript.

[01:45] The question you send to the model is a strongly typed question that must return a specific shape. One of three shapes actually, a choice, a score, and a null, which is basically just a yes or no. Its schema matching is guaranteed, and a type error would be mathematically impossible to produce.

[02:01] They call Jev a System 1 model, which is a name that comes from Daniel Kahneman's Thinking Fast and Slow. A System 1 model is fast and goes from gut instinct, while a System 2 model is slow and deliberate, it, like these old antique reasoning models like GPT-6 and Claude Fabel that burn 40,000 tokens to

[02:18] name a variable. But the difference is huge for app developers like myself who want to integrate fast, cheap AI into their applications. Like on Horse Tinder, we recently had an issue of some donkeys trying to use the app, which is strictly forbidden in the terms of service. Thanks to Jeff,

[02:32] we implemented an AI moderation step that will insta-ban any account that is not a horse, which is accomplished by returning a null response to is this a horse Not only is it extremely fast if we are to believe these TMBBs but more importantly it off the charts cheap like 440 times cheaper than one of the big brand

[02:49] models. In fact, it's so fast and cheap that you can even use it for real time applications, like developers are already using it to implement NPC behavior in video games. And this guy even used it to build the world's first real time AI calculator. But just because the output is type

[03:04] save, that doesn't mean it's always correct. And it's not even deterministic, like you could send at the exact same question in the exact same context and get different results, just like any regular large language model. But to get an idea of the response quality, it returns something

[03:18] called the calibrated confidence number. CHAP models are trained to police human raters, and humans love confidence, which is how we got models that are wrong with the confidence of Kanye. JEP gained its confidence through a technique called RLCD, or reinforcement learning

[03:31] for calibrated decisions. This means every response provides a confidence value, like say 60%, which means 60% of the time, it's right every time. But the big question is how does Jev actually work?

[03:43] Well, nobody knows for sure, because the CEO says the architecture is staying close to the chest, with a paper possibly coming in the future, maybe. But Jev also has some doubters. Some people say it's no different than zero-shot classifiers of the past,

[03:55] but the company gives no credit to the original pioneers of this technique, like Jin Yang who were building zero classifiers over a decade ago In addition this guy claims his paper he released a year ago is the exact same thing as Jev and another developer already built OpenJev which reproduces the entire interface by reading option probabilities off a frozen

[04:14] QEN4B model in a single forward pass. It requires no new training and can run on a 3090, and there's even a web GPU demo you can run in your browser right now. It's an awesome time to be a developer, which is why you need to check out Mux, the sponsor of today's video. Their

[04:27] highly customizable API is by far the easiest way to add video features to your application without getting jump-scared by FFmpeg. We've used it for years to handle all the hosting and streaming for our courses, but it does a lot more than just infrastructure. When you upload a video

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[04:58] you needing to host a model or maintain a pipeline. You can automate all this with directives, where you define a workflow once and it runs on every new upload, and you only pay for the jobs that actually run. Perplexity, Patreon, and many other prestigious companies all trust Mux, and their free

[05:13] plan includes 10 videos and 100,000 delivery minutes per month with no credit card required, and you can get an extra $50 credit at the link below. This has been The Code Report, Thanks for watching, and I will see you in the next one.

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