Testing framework

It reads like a test.

await each action
expect waits for the app
no sleeps, no YAML

import { test, expect } from '@simbase/test';

test('user can start charging their EV', async ({ app, given }) => {
  await given.fixture('ev', { connected: true, battery: 42 });

  await app.tap('ev-card');
  await app.tap('start-charging');

  await expect(app).toBeOn('/ev/charging');
  await expect(app.node('charging-status')).toHaveText('Charging');
  await expect(app.request('POST /charging/start')).toHaveStatus(200);
});

One test. Three layers. One page.

checkout.sim.ts

In-app
Taps and reads run inside the app.
tap ≈ 2ms
Visual
Named screens compared with a baseline.
diff per checkpoint
Black-box
Touch from outside, like a person.
tap ≈ 330ms

One evidence page, a verdict per layer

Where the time goes.

5–8×

faster per scenario

6.8s→1.1s

a six-step scenario, warm iPhone simulator

Seconds per phase, from outside versus in-app
Phase	From outside	In-app
Reach the start	1.1s	0.15s
6 taps	2.0s	12ms
6 waits	3.6s	0.98s
Reads	0.20s	2ms

Desk estimate. Taps and reads are measured; in-app reset and settle on real apps are targets we’ll measure and publish.

Failures say where.

Each step is a screen. The whole journey is checked, not just the last one.

checked at every settle · no crash · no 5xx · POST /orders at most once

Passed:
log in
/home
Passed:
open the product
/product/kettle
Failed:
add to basket
/basket
Not run:
pay
/order/confirmed

✗ add to basket · expected /basket, still on /product/kettle

Snapshot, network and console attached.

An optional SDK. About ten lines.

Name your routes, fixtures and state. The same calls on every platform.

Swift

#if DEBUG
SimbaseTest.route("ev/charging") { EVChargingView.present() }
SimbaseTest.fixture("ev") { p in
    EVStore.shared.seed(connected: p.bool("connected"))
}
SimbaseTest.reset { EVStore.shared.clear() }
#endif

React Native

if (__DEV__) {
  SimbaseTest.register({
    navigation: navigationRef,
    state: { ev: () => store.getState().ev },
    fixtures: { ev: (p) => store.dispatch(seedEv(p)) },
    reset: () => store.dispatch(resetAll()),
  });
}

Kotlin

if (BuildConfig.DEBUG) {
    SimbaseTest.route("ev/charging") { EvChargingActivity.start(it) }
    SimbaseTest.fixture("ev") { p -> EvStore.seed(p.bool("connected")) }
    SimbaseTest.reset { EvStore.clear() }
}

Debug only
Not in release builds. No flag turns it on.
Fails closed
No run token, nothing listens.
Redacted in the app
Only what you register. Secrets never leave.
Can’t cheat
No SDK taps. State is read-only.

Questions.

Can I use this today?

Not yet. It’s in development. The beta runs builds with explicit steps, as the docs describe.

Do I have to add the SDK?

No. Without it you still get taps, the screen hierarchy, settle, network and console. The SDK adds routes, fixtures, state and events.

Do my existing runs change?

No. The framework uses the same devices, evidence pages and PR comments.

Is it open source?

The in-app runtime and the test API are planned as MIT. The black-box drivers and the fleet stay closed.

Start with explicit steps today.

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