found the perfect use case for @typesafeai Jev: instant compaction in 2026, why is compaction still a summarization prompt? Jev can make it instant by scoring every tool call and dropping what’s irrelevant
jev-leftpad
A joke npm package that left-pads a string by asking Jev to choose among space_0 through space_10 in one Choice, spending a model call where padStart() would do.
- Category
- Cookbooks & Demos
- Published by
- Community
- Author
- f
- Added
- 2026-09-22
Tagscommunityjavascriptdemoplayground
Highlights
- Each call sends one Choice with criteria named space_0 through space_10; JavaScript then creates the chosen number of spaces.
- It can add between 0 and 10 spaces only, and the README notes Jev has no correct option beyond ten.
- One TypeSafe API request per call with retries disabled; the README says not to use it in production or anything important.
- Uses jev-latest through the official @typesafe-ai/sdk and requires Node.js 20 or newer and TYPESAFE_API_KEY.
Quickstart
ts
import leftPad from 'jev-leftpad';
const result = await leftPad('jev', 8);
console.log(JSON.stringify(result));Watch out
MIT-licensed. Needs Node.js 20+ and TYPESAFE_API_KEY, makes a paid API request per call, and is explicitly a joke package.
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From the community
Posts from builders shipping with Jev right now.
Instant compaction with Jev
A Claude session from 1M to 86K tokens
This is actually insane. This uses @typesafeai Jev model, as a plugin in Claude to review all the un-nesseasary tool calls, and it takes 1s to run! Like, literally, 1 second to take my Claude session from nearly 1M to ... 86K tokens! 😮 Ask your claude to install it and be Show more
found the perfect use case for @typesafeai Jev: instant compaction in 2026, why is compaction still a summarization prompt? Jev can make it instant by scoring every tool call and dropping what’s irrelevant
Vercel's fx safety reviewer, 18x faster
We're seeing extraordinary results from @typesafeai. Default mode in 𝚏𝚡 is auto, with a safety reviewer analyzing every command. That reviewer runs on GPT Luna today. Jev is up to 18x faster (p95) *and* more accurate. It's coming to @vercel AI Gateway and likely new default.
@fazxes
We benchmarked fx auto mode (safety) classifier with @typesafeai's Jev. tl;dr: ~5-18x faster and more accurate than 𝚐𝚙𝚝-𝟻.𝟼-𝚕𝚞𝚗𝚊, our current top choice
Jev lands on OpenRouter
Jev by @typesafeai is now on OpenRouter, in beta. Jev is a System One model. Instead of generating text, it takes your app's state plus a typed question and returns a typed decision with a probability attached. There is no JSON prompting, parsing layer, and nothing to validate Show more
700 leads scored for $0.09
JEV is INSANE. We gave it 700 high-intent leads and personalised outreach messages. In 40 seconds, it predicted how each message would perform, assigned a confidence score and detected lead-message mismatches. All for just $0.09. JEV can also score leads, analyse buying Show more
Beating Gemini Flash Lite on an eval
Ran @typesafeai's Jev against an existing classifier eval that previously used Gemini 2.5 Flash Lite. It won both on quality (saturated the eval) and speed (6x)
