SkillBenchmarks and evals
tenbin
Split a judgment into Choice, Score and Noul, lint it, then measure it.
Shingo Imota
4Updated Nov 10, 2026
What people are building with Jev
855 projects, posts and guides about Jev, the System One model from TypeSafe AI. Each entry links to its source and shows the cost and speed its author reported.
- 855builds
- 181guides
- 21use cases
Diogo Almeida
@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 cheaper (w/ output tokens free) • Frontier composable intelligence optimized for decisions AFAICT the shortest path to AI-based economic revolution
Our guidemadewithjev.com
Can you fine-tune Jev?
No: TypeSafe has not released the weights. What works instead — a $17 fine-tune on Qwen3.5 4B, a $95 open reproduction, and the 14 replicas and no-training methods already in this directory.
SkillAgents and browsers
Augustus
An agent skill for designing systems around Jev’s judgments.
Basit Mustafa
12
SkillRouting and model choice
switchloom
Deterministic model routing for coding agents, with a skill for Codex.
Instructa
1
SkillAgents and browsers
jev-superpowers
A skills framework for coding agents, with Jev gates and vetting.
Akash Priyadarshi
Guideflaviocopes.com
Jev: typed decisions, not text
Flavio Copes on triage, RAG filtering, citation checks and confidence thresholds.
SkillSDKs and integrations
Building with Jev
A skill for writing and fixing programs that call Jev.
Drew Breunig
155
GitHubContext and memory
jev-rules
Jev picks which of your rules apply, so Claude only sees those.
Elia Alberti
66
Fayaz Ahmed
@fayazara
Made myself a little image classifier with OCR + Jev It was able to categorise ~900 images in 40 seconds Pretty cool
Our guidemadewithjev.com
Can Jev read images?
Yes, since Jev 1.14: PNG and JPEG on jev-1.13.0 and jev-1.14.0 behind a header, plus a Box answer type. Not production-ready yet. The limits, the price, and when OCR or a vision model still wins.
Eugene Cheah - AI builder @ 🇸🇬|🇺🇸
@picocreator
love jev, but upset it - isn't open source? - it lack vision capability? We fixed all of that, introducing SimpleJev.ai A fully open source library which takes any HF model and Jev-ify it, with an API endpoint Now on github, and live in production at @FeatherlessAI
GitHubOpen source
Simple Jev
Daniel Ch
@chddaniel
Introducing Jev for 'Website to App' Turn any website into a native mobile app. Just paste a URL. jev-1.13.0 decides how to build the original website as a *native* mobile app, then shipper submits to the app stores for you. We’ve been using this internally a ton for iOS/Android apps.
XAgents and browsers
Website to App
Sawyer Hood
@sawyerhood
thanks to @typesafeai jev I no longer have fill out all of those fields on prompt boxes. It picks the agent / model / computer / folder for me. - For a major rewrite it uses Fable + Claude Code. - Changes to an ios app run on one of my macs
XRouting and model choice
A prompt box that fills itself in
Guideblog.lepine.pro
Let’s look at Jev
Jean-François Lépine on Choice, Noul and Score, calibrated confidence and batching questions, with a complete Python project.
Hamilton Ulmer
@hamiltonulmer
I made a DuckDB extension where you can use @typesafeai 's Jev to do quick classification of rows in any csv/parquet file or duckdb table about 10sec for 1k rows ~ better than using an LLM, way more ergonomic than a classifier game-changing for data analysis!
Steve Krouse
@stevekrouse
typesafe's jev is fun! live demo you can play with: typesafe-demo.val.run
GitHubAgents and browsers
Mobile Jev
A mobile agent on a real Android phone, with Jev making each decision.
Droidrun
4479 actions in ~21 sOur guidemadewithjev.com
Can Jev do maths, dates and counting?
No: TypeSafe documents nine jagged edges in Jev 1.13, including maths, counting, dates, long irrelevant state, injected text and option order. The fix for each, and the builds here that already work around them.
SkillAgents and browsers
Jev Browser Use
A Codex skill: Jev clicks, Codex thinks and checks the result.
coliney
1.2k~5–10×
GitHubSales and leads
Jev Recruiter
A LinkedIn recruiting agent that browses profiles and saves the evidence.
skeptrune
52
GitHubSecurity and abuse
Bouncer
A judgment layer that checks every Claude Code tool call against your policy.
Clownware
1~$0.04/day
Guidedev.to
How to use Jev: a practical guide
Valyu’s practical guide to TypeSafe’s System One model, on DEV.
GitHubAgents and browsers
Interlock
A gate on every agent tool call, with Jev as one of its sensors.
somoore
0
GitHubGames and real time
Jev Pong
Pong where the ball moves one step per model decision. Jev against the LLMs.
Ably Labs
1
GitHubGames and real time
Jev vs the LLMs: Tetris
Jev plays real-time Tetris against Claude Haiku or Gemini Flash.
Tony Dinh
20Our guidemadewithjev.com
Jev vs OpenAI Decisions API
Side-by-side: TypeSafe Jev (documented Choice/Score/Noul, confidence, GA) vs OpenAI Decisions on GPT-6 Luna (vision, public beta on OpenRouter). When to use which — no invented stats.
GitHubGames and real time
Kiru Hai Coach
A solo mahjong coach: Jev picks the tile to discard. In Japanese.
smilior
0
GitHubCoding and code review
Jev Review
A staged code-review workflow with a local dashboard.
Dev Agrawal
686
Guideskillsagentes.com
Jev de TypeSafe: qué es el primer modelo System One
Skills Agentes’ guide in Spanish: what Jev does, what it costs, what the evals say, and where it fits in an agent.
GitHubCoding and code review
Jev PR Labeler
GitHub PR labels chosen by Jev, with size measured as scope, not lines.
Jeremy Huang
4
GitHubCoding and code review
jev-oxlint
Turn an agent skill into an Oxlint plugin that asks Jev.
Tony Powell
1
