jevusecasesSubmit a project

What people replaced with Jev, and everything they're shipping with it.

Real projects, with the numbers to prove it. Open one to see how it was built.

Built something with Jev? Submit your project

Projects

1356 projects

Strongest evidencesecurity / guardrailsReplaces a paid tool: YES

jev-guard

Security classifier for coding-agent tool calls, rebuilt on Jev instead of a chat model.

See how it was built
Replaces
Claude Haiku 4.5 (as a tool-call classifier)
Against the baseline
3.4x faster, 28x cheaper vs Haiku 4.5
Cost signal
author reports 28x cheaper for the same tool-call classification task (unverified)
infra / open reimplementationReplaces a paid tool: KINDA

openjev-sglang

ReplacesTypeSafe's hosted Jev API

Open-source, Jev-compatible API that mimics Jev's fast parallel typed-decision behavior on an open model.

@ekzhang1How it was built
dev tooling / CLI

JevNQL

Against the baseline4.6x fewer rows sent to Jev than the same query unoptimized (730 instead of 3,345), 91 s down to 21 s

A query language and engine that mixes arithmetic and judgment in one query, such as the biggest spenders who seem increasingly unhappy about pricing. The arithmetic runs in Apache DataFusion and only the judgments go to Jev. Plain-English questions are turned into queries first.

@adityakhalkar_How it was built
browser agents / automation

Browser Use + Jev Ultrafast

Latency7.1 s

Open-source browser agent that found a real Google Flights result (Zurich to London) in 7.1s for $0.0039.

@gregpr07How it was built
trading / on-chain agents

Jev Trader

Latency81 ms

Trading bot that decides buy/sell on a live price feed and executes real on-chain trades on Monad via Kuru's order book, one decision every ~300ms block.

@jarrodwattsHow it was built
security / supply chain

pkg-gate

Latency100 ms

Pre-install security gate for npm packages that screens for malicious lifecycle scripts.

@GNUmanthHow it was built
dev tooling / IDE

The LazyIDE

Latency318 ms

Desktop AI IDE that uses Jev to route work to the right coding bot instead of guessing, and to triage incoming noise on wakeup.

@LazyIDEHow it was built
novelty / jokeReplaces a paid tool: NOT REALLY

is-jeven

Replacesthe % operator

Novelty npm library that checks whether a number is even by asking Jev.

@wobsorianoHow it was built
dev tooling / library

@adaptive-ds/jev

Gives TypeScript developers a client library and a jev command-line tool for TypeSafe System One. Calls return Results instead of throwing errors.

How it was built
dev tooling / library

@nu-sync/effect-evaluation

An Effect-native TypeScript client for TypeSafe System One models. It has typed failures and test layers.

How it was built
dev tooling / library

@underactive/jev-shim

Gives Node.js apps typed Jev classifiers and an OpenAI-compatible chat-completions facade.

How it was built
agent tooling / skills

@y0usaf/typesafe-mcp

An MCP server that gives coding agents access to Jev.

How it was built
trading / on-chain agents

15-min BTC JAP

Trades Kalshi's 15-minute BTC YES/NO market from live Coinbase data, with at most one $2 order per window.

How it was built
games / interactive

1v1 Jev

Runs a browser FPS where players fight an AI opponent in 1v1 matches to 5 kills, while spectators watch.

How it was built
games / interactive

2048

Runs the 2048 game in Python with a browser UI where you can watch an AI player choose moves.

How it was built
novelty / joke

A hundred faces

Shows a wall of one hundred invented people who react to a message while you type it.

How it was built
agent tooling / skills

a0-typesafe-ai

Adds typed Jev tools and probability cards to the Agent Zero chat as a community plugin.

How it was built
routing / model selection

A3M Router

Adds a remote backend for Jev-compatible endpoints to a deprecated LLM router.

How it was built
agent tooling / skills

Abide

Makes Claude Code, Codex, and opencode agents follow the rules in AGENTS.md and CLAUDE.md. It tells the agent which rule it broke so it fixes it.

How it was built
dev tooling / CLI

ActionJev

Code review for GitHub Actions and Gitea Actions, written in Rust. It posts a PR summary and writes JSON and Markdown reports.

How it was built
security / guardrails

actionreflex

Checks each AI agent action before it runs. It is a Python gate that you put in front of tool execution.

How it was built
content moderation / classification

adjudge

Blocks ads without a filter list. It is a Chrome extension.

How it was built
dev tooling / library

Advocaat

A small TypeScript client that asks Jev questions about your data in one request.

How it was built
routing / model selection

AegisCortex

Runs a local studio for a speculative AI control plane that handles routing, as a FinOps workbench.

How it was built
security / guardrails

Agent Action Guardrail

Checks proposed AI agent actions before they run and returns ALLOW, REVIEW, or BLOCK.

How it was built
security / guardrails

Agent Guard

Checks actions before tools run in Codex, Claude Code, or Devin CLI. You set the rules in plain language.

How it was built
routing / model selection

Agent Switchboard

Adds action gates and decision routing to AI agent harnesses, with paired cost and reliability evaluations.

How it was built
routing / model selection

Agent-Gantry

Adds a JevSelector to a Python library that finds and runs the right tools for LLM agents.

How it was built
agent tooling / skills

agent-gate-loop

A GitHub Action where an AI agent turns an issue into a pull request. A gate checks the change before a human sees it.

How it was built
security / guardrails

agent-guard

Checks Claude Code tool calls, such as Bash commands and file edits, before they run.

How it was built
games / interactive

Agent-JEV-Tetris

Tetris where Jev chooses every move and the game code does the math.

How it was built
agent tooling / skills

agent-workflow-typesafe

An external Agent-Workflow plugin that adds optional, advisory Jev evidence to bounded decisions.

How it was built
trading / on-chain agents

AgentArena

Runs an experimental protocol where AI agents play games on the Arc blockchain for USDC stakes.

How it was built
security / guardrails

AgentGhost

Intent-aware authorization for AI agent tools. It wraps tool execution, so each consequential action passes a check before it runs.

How it was built
agent context / memory

AgentKB

A personal, local-first memory system for coding agents. It uses Jev to triage demand signals.

How it was built
security / guardrails

agentOS

Runs an agent-first Linux operating system as a Debian ARM64 virtual machine with a tiling terminal.

How it was built
infra / open reimplementation

AI Backends

Adds a /api/evaluate decision endpoint to a self-hosted API server for common AI tasks.

How it was built
dev tooling / CLI

AI CLI Launcher

Launches AI coding CLIs such as Claude, Codex, and Gemini with preset flags from one menu.

How it was built
apps / personal tools

AI Column

Adds AI columns that need human judgment to an uploaded CSV. You review unsure rows and export the result.

How it was built
exploration / benchmarking

AI Elo Ranker

Ranks texts such as poems, pitches, and cold emails in an Elo tournament with Swiss matchmaking and a live dashboard.

How it was built
exploration / benchmarking

AI Fraud Control Room

Next.js demo that compares Jev with a Claude prompt-and-parse path on the same fictional payments.

How it was built
content moderation / classification

AI News Aggregator

Adds a Jev adapter to the relevance step of a multi-agent pipeline that publishes daily AI news briefings.

How it was built
browser agents / automation

AI Pentest Workbench

An Electron browser controlled by a JSON CLI for LLM-assisted, authorized web security testing.

How it was built
dev tooling / library

AI Provider for Jev

Connects WordPress to Jev as a plugin for structured decisions.

How it was built
trading / on-chain agents

ai-hedge-fund

Adds Jev as a model provider in an educational AI hedge fund proof of concept. The project makes no real trades.

How it was built
routing / model selection

Ailerix

Routes each model request to a provider through one public slug, ailerix/auto, as an OpenRouter alternative.

How it was built
security / guardrails

AiWrangler

Checks the plans and diffs of a coding agent against the project documents. Deterministic checks run first, offline.

How it was built
browser agents / automation

Almond-fastloop

Browser computer-use loop from Almond, plus the Browser Use Olympics benchmark it is measured on.

How it was built
agent tooling / skills

Android Control

Lets AI assistants control Android devices over ADB through an MCP server.

How it was built