JevPilot

What it does

JevPilot, by Justin Schroeder and published under Standard Agents, is a browser driving simulator built with Three.js. You can drive yourself, or press J and let Jev drive a route from one town, onto an interstate, and off into another, down to a final stop.

The design keeps nearly everything in code. The simulator samples candidate steering-and-speed paths, filters out those that leave the road or collide, and sends Jev compact tables of the eligible paths, road boundaries, nearby traffic, signals, and destination guidance. Jev picks the path. A safety brake in code handles imminent collisions, and questions with only one eligible answer are resolved locally without a request. Decisions run up to four times a second near traffic and about one and a half times a second on open road. A JSON panel shows the exact request and the probabilities that came back, and a Candidates view draws every path Jev chose from.

Setup

Run it locally with your own key:

npm ci
cp .env.example .env   # set TYPESAFE_API_KEY
npm run dev            # http://localhost:5173

Local mode skips sign-in and credit limits, keeps the key on the local server, and lets you drive manually without a key. There’s also a hosted version: sign in with Standard Agents and you get $0.25 of Jev credit, metered by the server so the key never reaches your browser.

Using it

• The build works, but not all tests pass. The production build completed. The offline test suite passed 36 of 47 tests. The 11 failures, covering road graphs, collision prediction, signals, and the decision format, repeated identically on every run. They’re offline tests, and the repository has no CI, so it’s worth running the tests before building on this code.
• The live loop works. The repository’s headless driving script runs the simulator with real Jev decisions. We ran it for 15 decisions: each request returned a choice, the controls were applied, and the script logged speed, safety events, and cost for every step. As with all our reviews, we don’t report how well Jev drove.
• Requests are compact by design. Shared values are sent once, instructions include only the situations that apply, and the full road graph is sent only when the car needs a new route. It’s a useful model for keeping a high-frequency Jev loop affordable.

Permissions and data

• Only simulation state goes to TypeSafe. Requests contain the simulated scene: paths, traffic, signals, and route guidance. Your own data isn’t involved.
• The hosted demo uses an account. Signing in goes through Standard Agents’ platform. The server sets a secure, HTTP-only session cookie, checks request origins, and keeps the Jev key and your credit balance on its side.
• The early-access box is pre-checked. The sign-in page’s “Add me to the Standard Agents early access list” checkbox is checked by default. The README says joining is optional, so uncheck it if you don’t want to join.
• No license. The code has no license file. The 3D models and textures in public/ carry their own licenses and attributions.

Maintenance

All fourteen commits landed on September 17, with thorough hosting documentation and helper scripts for browser and live checks. There are no issues or pull requests yet. It reads as a polished demo rather than a maintained library.

Verdict

JevPilot is a genuinely engaging Jev demo, and its architecture is worth studying: sample and filter in code, send Jev a small, well-shaped choice, and keep a safety layer underneath. Play the hosted version or run it locally with your own key. If you want to build on it, ask the author about a license first, and expect to fix the failing tests. For other real-time demos, see TypeSafe Mario and jev-trader.

See how it compares with other tools in Best Jev tools, tested hands-on.

Review updated Sep 19, 2026. Numbers quoted from the project are its author's own; we don't publish our own measurements of Jev.