Question 1

Does this put my API key in the browser bundle?

Accepted Answer

Not with the documented path. `jev-ui/action` is a ready-made Server Action that reads `TYPESAFE_API_KEY` on the server, so the browser never sees it, and the README tells you to add `.env` to `.gitignore` before pasting the key in. If the environment cannot express what you need, `createResolver` from `jev-ui/server` lets you write your own action with a custom transport, per-request model or pricing table.

Question 2

What can this actually decide, and what can it not?

Accepted Answer

It picks what renders: `Branch` selects one subtree, `Rank` orders, filters and truncates a candidate set, and `Gate` shows an affordance when a condition holds. `useScore` answers how much, for use as an ordinary prop such as row count or table density. Nothing here submits a form, spends money or deletes a row, and `Gate` can only add because hidden content is an accessibility and SEO problem.

Question 3

I need typeahead over thousands of rows. Is this slow or expensive?

Accepted Answer

Typeahead is `Rank mode="compete" take={4}`: your code finds the candidates and the judgment only picks among them, so the model never sees the full list. Every judgment in one render pass collapses into one request because state is ingested once for all of them, which is also why the marginal question is close to free. Each component reports what that render cost through `onResolved`.

Question 4

How do I test this without burning API calls?

Accepted Answer

`JEV_TRANSPORT` takes live, record, replay, mock or auto, and defaults to live when a key is present and replay otherwise. `record` writes fixtures and `replay` reads them from `JEV_FIXTURES_DIR`, which defaults to `fixtures`. The state you send also matters: three layers merge local over scope over ambient, with the library supplying `recent_actions` and `time_spent`.

Question 5

What do the four environment variables do, and how do I set them up?

Accepted Answer

TYPESAFE_API_KEY is server-side only, JEV_TRANSPORT takes live, record, replay, mock or auto and defaults to live with a key or replay without one, JEV_MODEL defaults to jev-latest, and JEV_FIXTURES_DIR defaults to fixtures. Put the key in .env at the root of your Next.js app and add .env to .gitignore before you paste it in; Next.js and bun both load .env on their own, so there is nothing else to configure.

Question 6

How does state get to the model, and what does the library add?

Accepted Answer

Three layers merged local over scope over ambient. The library supplies recent_actions and time_spent as ambient state, you set app.* at the provider as scope, and data.* at the call site as local. The state prop is live rather than an initial value, so it can come from Redux, a session or a server prop and the provider syncs each key whose value changes; onStateChange fires after every change if you want to persist it.

Question 7

Why do numeric values get turned into words before the model sees them?

Accepted Answer

Because Jev underperforms on numeric representations and does not count reliably, so 41200 ms is projected to time_spent: "long" before it is sent. Banding also keeps re-resolution rare, since a value inside the same band produces the same judgment. MIT licensed, and running the demos yourself with your own key in apps/demo/.env makes each one call the real API rather than a fixture.

Jev UI

About this project

Highlights

Questions about this entry

More Jev resources like this

From the Jev community