Read & learn
Written guides.
Understand Jev, one idea at a time. Walkthroughs, recipes, and writeups — our notes first, the original next.
Explore the Jev ecosystem.
Learn, build, and play with Jev — from deep technical guides to creative experiments.
Watch & learn
Video guides.
See an idea take shape. Tutorials, demos, and deep dives, organized by topic and credited to their creators.
Make & explore
Experiments.
See what builders made with Jev. Games, tools, repositories, articles, and more — traced to their sources.
The directory03 / 03 · Experiments
Find something worth exploring.
Every category, from games and tools to repositories and writeups, traced to a primary source.
Same ideas.
Different paths.
This is the full registry, not just the featured picks. Figures like speed, cost, and stars are maker-reported or captured snapshots, not JevMade measurements.
379 experiments · showing 121–180
An AI player tackles Unreal Tournament 99 on a real Windows 98 machine.
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from the source
move: choice("What movement should the player take right now?", { advance: "Move forward, toward the objective or nearest enemy.", retreat: "Move backward, away from danger.", strafe_left: "Strafe left.",
A self-running browser instrument that asks Jev which musical scene, harmony, phrase, riff and timbre should arrive next.
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from the source
export const KINDS = { scene: { next: { type: 'choice', instructions: SET + 'Choose the scene that should come next so the set keeps developing over tens of m...
A 3D character whose movements, expressions and gaze are chosen by Jev.
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from the source
for (const m of MOTIONS) { questions[m] = { type: 'noul', instructions: `The user just said to the robot: "${msg}". ` + doing
Two Jev brains perform a fixed piano piece, choosing hand and finger positions for each 100-millisecond slice ahead of time.
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from the source
A hand has a fixed span and five fingers that never cross. A note sounds only if a finge...already resting on that exact key when its moment arrives. Every 100 ms slice of the pie...question to [TypeSafe's Jev](https://docs.typesafe.ai/introduction): where does this han...and which key does each of its fingers rest on. Jev answers with option ids from the lis...offered, never a key name or a coordinate.
Pitch an invention to three fictional judges and try to win their votes.
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from the source
const result = await client.systemOne({ state, questions: Object.fromEntries( person.criteria.map((c) => [ c.id,
A pixel-art experiment that asks Jev to choose the colors from a short brief.
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from the source
export const BRIEF_QUESTIONS = { boundary: { type: 'score', criteria: VERT, instructions: "Where, top to bottom, does the main boundary between the picture's tw... focal_present: { type: 'noul', instructions: 'Does the picture have one clear focal object that the eye goes to fir...
Three experiments in making color themes, photo grades and charts from Jev's decisions.
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from the source
import { choice, score } from "@typesafe-ai/sdk";export const HUE_ANGLES: Record<string, number | null> = { red: 25, orange: 55, yellow: 95,
Turn a 3D Rubik’s Cube yourself while Jev decides when to coach you, stay quiet, or offer a demonstration.
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Enter a Korean name and see Jev choose the most likely age band for it in a small React experiment.
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Change a robot’s sorting rule, take over a game, or inspect Jev’s choices in DriftLoom’s eight-demo playground.
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Jev chooses moves for a playable version of Tetris.
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A small browser game challenges players to outguess Jev.
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from the source
npm installnpx wrangler loginnpx wrangler secret put TYPESAFE_API_KEY # required before the first deploynpx wrangler deploy # → https://beatjev.<you>.workers.dev
Jev controls the paddle of a Next.js brick-breaker in real time.
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Play either side of a browser chessboard while Jev chooses the opposing moves from structured board state.
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An endless Three.js cyberpunk arena shooter uses Jev to drive combat decisions.
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from the source
┌───────────────────────────┐ │ TypeSafe AI Jev Model │ │ (or Local RLCD Engine) │ └─────────────┬─────────────┘ │
A game about linking two seemingly unrelated things in as few steps as possible.
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Arrive in a village of Jev-driven characters and earn their trust before nightfall—or try to get away with a lie.
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A hundred AI residents go about their lives in a tiny town, with Jev choosing what each does next.
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from the source
Jev Lab ├── Hundred 100 people, one town └── Jev Shogi human Sente, Jev Gote
Jev Arcade pairs an industrial duel with a neon survival game, both playable against live AI.
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Play tic-tac-toe or Connect Four against Jev while conventional code enforces the rules.
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A terminal tool races through Wikipedia links by asking Jev to rank each possible next page.
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from the source
git clone https://github.com/komikat/jev-bfs.gitcd jev-bfsuv sync --lockeduv run jev-bfs --install-browseruv run python -m unittest discover -s tests -v
A visual lab runs Jev and scripted agents across several games and emulator platforms.
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from the source
uv run jev-games play --game mario --policy scripted --decisions 20uv run jev-games play --game kungfu --policy scripted --decisions 20uv run jev-games play --game doom --policy scripted --decisions 20uv run jev-games play --game mario --policy jev --decisions 10
A MoonBit playground for trying Jev's Choice, Score and Noul question types.
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noul
This message is spam.
Jev plays browser table tennis from structured telemetry and sends its choices through ordinary Chrome inputs.
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Jev plays Snake by reading the board and picking a direction on every tick.
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from the source
snake_game/├── game.py # pure game rules and state transitions├── jev_agent.py # typed Jev adapter├── state.py # game state -> JSON-compatible AI state├── config.py # defaults and environment overrides
Jev plays the Chrome dinosaur runner.
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A playable Tetris asks Jev to choose each piece's rotation and column from the board state.
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Spawn Minecraft bots and give them goals, with a planner choosing the task and Jev handling the immediate actions.
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A cyberpunk game of bluffing your way past a border guard powered by Jev.
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A cooperative platform shooter puts a Jev-controlled partner beside the player.
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Jev plays Atari Pong by answering one movement question per frame without receiving raw coordinates.
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from the source
bridge/pong_bridge.py ALE/Pong-v5 behind a JSON step APIsrc/core.ts arithmetic, wording, the question, the baseline policysrc/jev.ts TypeSafe System One client, one POST, no SDKsrc/bridge.ts HTTP client for the environmentsrc/agent.ts the play loop, emits ticks and never prints
An autonomous agent plays PlayStation 2 games while a live HUD shows Jev's visual telemetry.
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from the source
export TYPESAFE_API_KEY="your_api_key_here"export TYPESAFE_MODEL="jev-latest"export EMULATOR_WINDOW_TITLE="PCSX2"export TARGET_FPS="30"
Jev supplies the decisions for non-player characters living in a simulation of River Oaks, Houston.
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A Jev pilot flies through a Python river shooter inspired by Atari's River Raid.
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from the source
.venv/bin/python -m typesafe_pilot # watch it play in r....venv/bin/python -m typesafe_pilot --lockstep # game waits for eac....venv/bin/python -m typesafe_pilot --headless --frames 3000 # no window, prints....venv/bin/python -m typesafe_pilot --record play.mp4 --seconds 60 # save a video with....venv/bin/python -m typesafe_pilot --human # fly it yourself (n...
A 3D planetary rover sandbox tests autonomous choices made with TypeSafe AI.
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Jev moderates a living-room social-deduction game designed for a shared television.
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Two hundred people try to break an agent's defenses while a defender uses each breach to improve them.
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Jev considers several questions about the board at once to choose Snake's next move.
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from the source
git clone https://github.com/siroccomask/snake-jev.gitcd snake-jevuv synccp .env.example .env
Jev presses the controls of a small virtual creature while deterministic code runs its world.
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Play either side of a 3D chessboard against Jev, or watch two Jev players face off.
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Two Jev agents play chess, choosing every move through a typed Choice question.
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Jev controls a Minecraft Java player through tasks such as gathering lumber and building a Canadian flag.
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from the source
{ "model": "jev-latest", "state": { "scenario": "lumber", "goal": "Find trees, collect 10 new logs, then return to the starting position.",
CartShield assigns a fraud disposition to checkout activity for small online shops.
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Crowdcheck simulates how 10,000 AI readers might react to a post before publication.
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Twelve deliberately unqualified AI councillors vote on unusually specific questions.
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from the source
TYPESAFE_API_KEY=your-key-hereTYPESAFE_MODEL=jev-latest
Harness Judge labels each agent step as acceptable, worth retrying, needing escalation or ready to stop.
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HireSignal gives resumes a first-pass fit assessment and an interview recommendation.
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Human Compiler turns prose into compiler-style diagnostics for traits such as passive aggression and corporate jargon.
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from the source
Compiling input.txt (--mode corporate) Lexing 0.4ms 4 paragraphs, 7 sentences, 62 words Analyzing 812ms jev-1.13.0, 45 questions, 1203 tokensPASSIVE_AGGRESSION ████████░░ 0.82CORPORATE_BULLSHIT █████████░ 0.94
Upload a dataset, pose a question and watch Jev classify every row.
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from the source
CONVEX_URL=https://<deployment>.convex.cloudCONVEX_WRITE_SECRET=<operator-provisioned-secret>CONVEX_DEPLOY_KEY=<Convex production deploy key, Vercel Production only>OPENROUTER_KEY=<operator-provisioned-secret>JEV_API_KEY=<operator-provisioned-secret>
A 3D robot companion reacts through typed Jev decisions rather than generated dialogue.
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An interactive room changes in response to the visitor's words, using presets or live Jev decisions.
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A public demo uses Jev to review an advertisement before it runs.
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An interactive workspace for browsing Jev Board datasets and asking Jev questions about them.
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A first Jev tutorial in TypeScript and Bun, starting with the question of whether a hot dog is a sandwich.
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from the source
# Playground の Noul のサンプル「ホットドックはサンドイッチか?」を API でbun run noul1bun run noul2 # placefolder 使用bun run noul3 # 並列問い合わせ# noul1 を改造して、日本語のテスト「バナナはおやつに入りますか?」
A Dart collection tests Jev across several small demonstrations.
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A single screen compares Jev and an LLM on emotion shifts and response speed for the same statement.
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Jev Paper Judge gives rapid feedback on an academic paper.
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Jev chooses a musical plan from fixed options, then code renders the score, audio and MIDI.
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from the source
“Philip Glass” src/ │ style string ▼ ┌─────────────────────────────┐ Planner interface planner/Planner.ts │ JevPlanner │ Heuristic- │ plan(input) → CompositionPlan planner/JevPlanner.ts
A job-application demo that asks Jev whether a role is worth applying for.
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A public demo turns Jev into a jury for user-related decisions.
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Jev, briefly
A decision model, not a chatbot.
A chat model generates text token by token and hopes you parse it. Jev never generates a word. Your code sends the state of the world plus typed questions; Jev returns every answer in one parallel pass — typed values with calibrated probabilities and a confidence score your code can trust. About 70–500 ms end to end, $0.042 per million input tokens, output free. Trained with what TypeSafe calls Reinforcement Learning for Calibrated Decisions.
choice Pick one of these.
You define the options. Jev returns the chosen option, a probability for every option, and a confidence. The workhorse of routing, agents, and games — the answer space is always legal, so there is nothing to parse and nothing to hallucinate.
score Rate this on a rubric.
You describe ordered levels — say trivial / normal / critical. Jev returns the level, the probability of each, and a confidence. Scores turn fuzzy judgment (“how severe is this log line?”) into a number-free decision your code can branch on.
noul Is this statement true?
You assert a statement; Jev returns the probability that it is true — a noul. Moderation, verification, guardrails, “does this diff actually fix the bug?”: one question, one calibrated probability.
Official material lives at typesafe.ai and docs.typesafe.ai. JevMade is an independent community registry — not affiliated with or endorsed by TypeSafe AI.
Recurring lessons
Patterns that keep showing up.
One decision per tick
Games, drones, trading bots, and browser agents all converge on the same loop: serialize the state, ask one decisive question, act, repeat. Jev’s latency makes the loop feel instant — the model lives inside the control loop, not outside it.
Confidence as a gate
The answer says what; the confidence says whether to act. The most reliable entries threshold on confidence to route edge cases to a slower model or a human — automation with an honest escape hatch.
Shrink the choice space in code
Makers rarely ask Jev to pick from everything. Local tactics prune 225 gomoku moves to ~40; DOM filters turn a page into an element table; code narrows options, Jev judges within them.
Jev judges, LLMs talk
A recurring split: Jev makes every decision cheaply and instantly, and a small LLM is only invoked when a human-facing string must actually be written. Decision and generation are separate budgets.
Made something with Jev?
Send the link — repo, live demo, post, or video — plus a line on what it does and which primitives it uses. Every entry is verified against its primary source before it ships.
Submit your experiment → hello@JevMade.com