开源了 LitJev：我们对 Jev 类型化决策 API 实现方式的猜想，可接入任意现成 LLM。 小测试：Qwen3.8-27B，10 道 MMLU-Pro 一次完成，0.3 s。比让模型只生成答案快 2.9x；比生成完整 schema JSON 快更多（显然）。更多测试马上来。 非官方，基于公开信息。
API & Models
jev-latest
The default model alias in the SDKs and docs: the most recent stable official Jev release, currently jev-1.13.0.
- Category
- API & Models
- Also known as
- —
- Related terms
- 4
- Directory entries
- 2
- Docs
- docs.typesafe.ai
- Added
- 2026-09-24
Definition
jev-latest is the name most examples use and the SDK default, so omitting a model is equivalent to asking for the latest stable release. It points to jev-1.13.0 today.
It is an alias, not a version: the answers behind it can change when a new release ships. Pin jev-1.13.0 instead when you need reproducibility.
Tagsapimodels
Related terms
Definitions that connect to this one.
Model aliasA name like jev-latest that resolves to a versioned model ID and can move when a new release ships.API & Modelsjev-previewThe alias for the most recent Jev release whether or not it is official; currently identical to jev-latest.API & Modelsjev-1.13.0The current versioned Jev build: $42 per billion input tokens, a 64k context, and 250,000 tokens per second.API & Modelsmodel fieldThe required request field that selects which model handles the call; accepts versioned IDs and aliases.API & Models
From the directory
The model card for jev-1.13.0: $42 per billion input tokens with free output, a 64k context, 250k tokens per second, and how to list the models your account can call.
Sites & GuidesDocs#official#docs#models
Official
The canonical introduction: Jev is TypeSafe's flagship model and the first System One model. Send state and typed questions, get structured answers your code can use directly.
Sites & GuidesDocs#docs#official#primitives
Official
From the community
Posts from builders shipping with Jev right now.
LitJev: Jev-style decisions on any local LLM
Secret detection with Jev, tested
Built a quick Secret Detection Test with Jev by @typesafeai Results seem promising so far, ran it a few times and it's pretty consistent as well. github.com/teyhouse/jev-s…
Jev Driving Lab: a playground for System One models
@typesafeai (and System One models in general) have a lot of uses, and fun to play with. New paradigm open to public now. This is a self-driving sim I spun up to test Jev today. Structured sensor state in, typed driving decisions out, steer, brake, overtake, pedestrians, speed Show more
200 rows, 32 template families, and traps, judged in one call
First test with Jev (TypeSafe System One): 200 rows, 32 template families, traps — 'yes' rows with "we'll pass", 'no' rows with 'absolutely, happy to meet'. The single Jev question scored 100%. My 12 dimensions scored 98%. I had designed a task my own question could ace.
jev(): Postgres WHERE clauses in plain language
I think I just cooked something 🔥 jev(): a PostgreSQL extension that searches your whole database in natural language. No index, no embeddings, just one function. WHERE jev(people, 'could work from home') or WHERE jev(people, 'name sounds european') 129 rows judged in ~1s Show more
@CompleteSkeptic
After co-inventing ChatGPT, I kept asking myself: why have superhuman chat models not led to AGI? I’ve spent the last 2 years in stealth building a new way to train models (RLCD), and a new type of frontier AI model that we are releasing today: Jev • 20-200x faster • 40-400x
A real-time ad blocker that classifies every DOM element
I build an undetectable realtime adblocker extension with typesafe It checks every dom element and classifies as ad/non-ad and removes it if true Extremely fun to work with, expecting an incredible shift in how AI is being used in the future
@CompleteSkeptic
After co-inventing ChatGPT, I kept asking myself: why have superhuman chat models not led to AGI? I’ve spent the last 2 years in stealth building a new way to train models (RLCD), and a new type of frontier AI model that we are releasing today: Jev • 20-200x faster • 40-400x