The UI runtime for code you didn't write

A model can generate a BaseNative interface at inference time — no build step, and no escape hatch to arbitrary JavaScript. The expression evaluator never calls eval or new Function, and render() takes that generated template string and returns HTML on the spot.

Why this is different

A CSP-safe evaluator, a runtime template renderer, and a toolchain that lets the model check its own output before it ships.

CSP-safe expression evaluator — no eval, no new Function done
Model self-check — @basenative/validate, /mcp, /evals done
@if / @else conditional rendering done
@for list rendering with track done
@switch state matching done
Signal-based reactivity done
Server-side rendering done
Client hydration done
Expression binding (:attr, @event) done
SSR + hydration example done

Eval results: not yet published — the harness ships, the corpus is in progress.

How it works

Write standard HTML with template directives. BaseNative handles the rest — server-side or client-side.

Reactive counter in 6 lines

<button @click="incrementCount()">
  Clicked {{ count() }} times
</button>

<script type="module">
  import { signal, hydrate } from 'basenative';
  const count = signal(0);
  function incrementCount() { count.set(count() + 1); }
  hydrate(document.body, { count, incrementCount });
</script>

Server-rendered list with Express

// server.js
import { render } from 'basenative/server';

app.get('/', (req, res) => {
  const html = render(`
    <template @for="user of users">
      <li></li>
    </template>
  `, { users });
  res.send(html);
});

This is a supporting fact, not the argument — the CSP sandbox and runtime string rendering above are the reasons to use it.

no eval, no Function security boundary
template string at runtime render()
validate + mcp + evals self-check loop
9.2KB / 10KB budget @basenative/runtime (gzip)

Recent updates

Initial proof of concept complete 2025-01-15
Server renderer implemented 2025-02-01
Express example with SSR + hydration 2025-02-15
Signals playground added 2025-03-01
API documentation page 2025-03-15