Routing

Routes come straight from the filesystem under src/.

src/
  index.ht.js              → /
  about.ht.js              → /about
  blog/
    index.ht.js            → /blog
    [slug].ht.js           → /blog/:slug
  docs/
    [...path]?.ht.js       → /docs, /docs/a, /docs/a/b, ...
  (admin)/
    users.ht.js            → /users
  404.ht.js                → dist/404.html

Route table

Feature	File	URL
Static	`index.ht.js`	`/`
Nested	`blog/index.ht.js`	`/blog`
Dynamic	`blog/[slug].ht.js`	`/blog/my-post`
Multiple params	`blog/[year]/[slug].ht.js`	`/blog/2026/my-post`
Catch-all	`docs/[...path].ht.js`	`/docs/api/auth`
Optional catch-all	`docs/[...path]?.ht.js`	`/docs + deeper`
Route groups	`(admin)/users.ht.js`	`/users`

More specific routes win: static beats dynamic, dynamic beats catch-alls. Two files generating the same URL is a build error.

generateStaticParams

Dynamic routes declare which pages to emit at build time. In sitelo (dev), dynamic routes still render on demand without listing every param.

export function generateStaticParams() {
  return [
    { slug: 'hello-world' },
    { slug: 'my-first-post' },
  ]
}

export default ({ params }) => `
  <html><body><h1>${params.slug}</h1></body></html>
`

import { html, body, h1 } from 'javascript-to-html'

export function generateStaticParams() {
  return [
    { slug: 'hello-world' },
    { slug: 'my-first-post' },
  ]
}

export default ({ params }) =>
  html(
    body(h1(params.slug))
  )

export function generateStaticParams() {
  return [
    { slug: 'hello-world' },
    { slug: 'my-first-post' },
  ]
}

export default function Post({ params }) {
  return (
    <html>
      <body>
        <h1>{params.slug}</h1>
      </body>
    </html>
  )
}

Values can be strings, numbers, or booleans — they are stringified and URL-encoded. Catch-all params accept arrays ({ path: ['a', 'b'] }) or slash-separated strings ({ path: 'a/b' }).

A dynamic page that generates zero routes prints a warning so it cannot silently vanish from your site.