On this page
Concepts
These pages cover the building blocks of a Fresh application. Read them in order for a guided tour, or jump to what you need.
Routing & data
- Routing — turn files in
routes/into URLs, with dynamic params, catch-alls, and route groups. - Routes — what a route file looks like: handler + page, return values, GET vs POST.
- Context — the
ctxobject every handler and middleware receives. - Middleware — run logic before routes: auth, logging, shared state.
Rendering
- Layouts — wrap groups of routes in shared UI.
- App shell — the
<html>document around every page. - Error pages — render 404s, 500s, and thrown errors.
Interactivity
- Islands — components hydrated in the browser.
- Signals & reactivity — reactive state, on the page and inside islands.
- Event handlers — wire up
onClick/onInputwithout an island.