v1.9.2 — extensionless URLs, like GitHub Pages

Jul 28, 2026 | 2 min read

The dev server now resolves /a/b to a/b.html, so links written without the extension stop 404ing locally while working fine in production. The 404 page also loads its own styles at any depth, and serve.base "/" no longer 404s every request.

Fixed

The dev server resolves extensionless URLs. GitHub Pages serves /a/b from a/b.html without touching the URL. The local server didn't, so a link written as /changelog/v1.9.1 worked in production and 404'd on localhost:4040 — the one place you'd have caught it. Both agree now:
```
/a/b  →  a/b.html          200, URL stays /a/b
/a/b  →  a/b/index.html    301 to /a/b/, then the index
```
The directory redirect was already there; the file fallback is the new part, and it only fires when neither a file nor a directory matches. Relative assets on those pages need nothing special — an extensionless URL sits at the same depth as the file behind it, so ../css/styles.min.css resolves the same for /changelog/v1.9.1 and /changelog/v1.9.1.html.
404.html loads its assets at any depth. The 404 page is the one file served from a path it doesn't live at: it sits at your site root but answers for /a/b/c/anything. Its relative asset paths — ./css/styles.min.css — then resolved against /a/b/c/, so a miss at the root rendered fine and a miss two levels down rendered unstyled. The server now pins them:
```
<head>
  <base href="/" />
  <meta charset="utf-8" />
</head>
```
Injected only when the page doesn't already declare its own <base>, and only in the response — your built 404.html is untouched on disk, which matters when you publish under a project path like /poops/.
serve.base: "/" no longer 404s the whole site. The server keeps every request inside its base directory by resolving the path and checking it still starts with that base. A base of / joins to <cwd>/ — with the trailing separator — so the check compared against <cwd>// and nothing ever matched. Every URL, including /, came back 404. The base is now normalized before anything is joined to it, so a trailing separator means what you'd expect. Traversal attempts are still rejected the same way.