Example

Tags

Paths in tags start at src/, the same as the URLs in the build.

Tag	Does
`<x-html src="partials/nav.html"/>`	Pastes in a partial, indented like the tag
`<x-js src="/js/index.js"/>`	`<script>` with a `?v=hash`
`<x-js src="/js/app.js" module/>`	One of your `modules`, with a modulepreload for each chunk it imports. `preload="/js/data/x.js"` adds one for a file it `import()`s later
`<x-css src="/css/index.css"/>`	Stylesheet `<link>` with a `?v=hash`
`<x-seo title="..." description="..."/>`	Title, description, canonical URL, link preview tags. `image`, `image-alt` and `image-size="WxH"` for its own preview, `section` and `name` for breadcrumbs in search results

A tag mothwing doesn't know, or one missing what it needs, fails the build with the page it's on.