jac-cl-routing

Create a pages/ directory where each file with a public export returning JsxPage becomes a route by convention. The filename sets the URL: index.jac maps to the directory root, about.jac to /about, and [id].jac to a dynamic :id segment.

File-based routing is the recommended default since files in pages/ become routes with no Router wiring. Manual <Router>/<Routes> suits apps wanting one explicit route table, but never mix the two systems in one app.

Place pages inside a route group folder named (auth)/ and the build system automatically wraps every page inside with an AuthGuard. The default unauthenticated redirect is /login, configurable via auth_redirect in jac.toml.

The most common cause is a main.jac app export that ignores its children argument, which silently drops every route while builds pass. Export def:pub app(children) that renders children inside JSX, such as a fragment or provider wrapper.

Use useParams() and access values by subscript like params["id"], since dot access fails and missing params return undefined. For query strings, parse useLocation().search with new(URLSearchParams, location.search).

Routing uses clean BrowserRouter URLs, so any production host must serve the app HTML for extensionless non-API paths. jac start handles this SPA fallback automatically when base_route_app is set, but other hosts need equivalent configuration.