Slots

Template slots

Slots are named injection points in the HTML template where plugins can insert content. There are six slots:

Slot	Position
`head-end`	Before `</head>` — for stylesheets and meta tags
`after-title`	After the article title and date
`before-article-end`	Before `</article>`
`after-article`	After `</article>` — for comments, related posts
`footer-right`	Inside the footer
`body-end`	Before `</body>` — for scripts and tracking

How slots work

During generation, moss writes HTML comment markers at each slot position:

<article>
  <h1>Page Title</h1>
  <!-- slot:after-title -->
  <p>Content...</p>
  <!-- slot:before-article-end -->
</article>
<!-- slot:after-article -->

During the enhance phase, each plugin with the enhance capability returns content for the slots it wants to fill. moss replaces the markers with the plugin content. Any unfilled markers are stripped from the final output — they never appear in the published HTML.

Multiple plugins can write to the same slot. Their content is concatenated in plugin load order.

EnhanceResult

The enhance hook returns an object mapping slot names to HTML strings:

async enhance(ctx) {
  return {
    slots: {
      "after-article": `<section class="comments">
        <script src="https://comments.example/embed.js"></script>
      </section>`,
      "head-end": `<link rel="stylesheet" href="/comments.css">`
    }
  };
}

Only include the slots your plugin needs. Omitted slots are left for other plugins or stripped.

Zero-flicker preview

During preview, moss rebuilds the site on every file change. To prevent the preview from flickering during rebuilds:

New output is built to .moss/site-stage/
The preview server atomically switches its pointer to site-stage/
The staged content is copied to .moss/site/ (the canonical directory)
The pointer switches back to .moss/site/

The preview server never serves from a half-built directory. The switch is instant — a pointer update, not a file rename.