Feature OS
Sign inGet started
Deterministic · immutable · local-first

Upload a component.
Get a spec your AI can build from.

Feature OS extracts design tokens, responsive strategy and a view-state map from the markup you already have, then emits a markdown spec you paste into your coding tool. The same input always produces the same file — byte for byte.

Create a workspaceNo credit card. Your files stay on your disk.
You have
<section class="pricing">
  <div class="tier" data-state="loading">
    <h3>Pro</h3>
    <p class="price">$29</p>
    <button>Choose</button>
  </div>
</section>
You get
# Pricing Table

## Design tokens
primary #3B82F6 · radius 12px

## View states
base, loading (0.92 confidence)

## Responsive
container-query · 420 768 1024

Deterministic

No model runs during extraction. The same markup produces the same spec every time, so a diff means a real change.

Immutable versions

Saving appends. Every spec records the exact prompt version it was rendered with, and nothing rewrites history.

Local-first bytes

Postgres holds structure and hashes. Your feature files live on your own disk, under storage/.

Four projects, four takes on the same form?

Collections

Group the builds and compare them across eight dimensions — coverage, responsive, accessibility, states, theme, structure, contract, validation. The scoring reads the extracted structure, so the ranking is identical every time and no model is involved. Each run is frozen with the weights it used, because a score is meaningless without them.