Step 1 — Routing

File structure is your URL structure. No configuration needed.

How it works

The What framework uses file-based routing. Every .html file inside site/ automatically becomes a URL. The directory structure maps directly to paths.

File → URL mapping

File

site/index.html
site/about.html
site/tutorial/1.html
site/blog/[slug].html

URL

/
/about
/tutorial/1
/blog/hello-world

Dynamic routes

Wrap a filename in square brackets to create a dynamic segment. The value becomes a #params.name# template variable.

<!-- site/blog/[slug].html -->
<what>
title: "Blog post"
</what>

<h1>#params.slug#</h1>

Visit /blog/hello-world and #params.slug# renders as hello-world.

Live proof

You're on /tutorial/1 right now. That URL exists because the file site/tutorial/1.html exists. Click any link below — each one is a file in site/tutorial/.

tutorial/1.html → /tutorial/1 tutorial/2.html → /tutorial/2 index.html → /

The <what> block

Every page can have an optional <what> block at the top. It sets the page title, layout, auth rules, and data fetching. It is stripped from the output — never shown in the browser.

<what>
title: "My Page Title"
layout: none
auth: user
fetch.posts = "local:posts"
</what>

What you learned

Files in site/ become URLs automatically
Directory structure maps to URL paths
[name].html creates dynamic routes, accessible via #params.name#
The <what> block controls title, layout, auth, and data — never rendered