Site Builder turns a description into a working, deployable browser application — not a static mockup. Open it from Build in the navigation.
Two ways to start
- Choose a template — vetted, responsive starting points that are editable straight away. Name the project and select Create project; it opens in Files ready to edit.
- Build with CruxAI — describe what you want in plain language and let CruxAI generate the whole project.
Writing a good build prompt
Describe the app in terms of what people do in it, not what it looks like. Compare:
- Weak — "a nice website for my photography business."
- Strong — "a client portal for a photography studio where clients sign in, see their galleries, approve selects, and download finals."
The built-in examples are good models: a collaborative launch checklist with owners and deadlines, a CRM with contacts and deals and a responsive dashboard, an event planner with RSVPs and a budget. Name the screens, the data, and who uses them.
Choosing how it builds
The model selector offers Fast, Think, and Pro across the CRX-4.1, CRX-3.5, and CRX-3.2 generations. CRX-4.1 Think is the default and the right choice for most builds. Use Pro for genuinely complex applications; the earlier generations are available on CruxAI+ if you need to match an existing project.
Attaching material
Before building, attach reference files from your Device or Crux Cloud — a logo, a brand sheet, a spreadsheet of the data the app should handle, a screenshot of a layout you want.
While it builds
CruxAI streams its build actions as it works so you can see what is being created. Larger projects take a few minutes. When it finishes, the project opens in the editor with a private preview — nothing is public until you publish it.