The sitespeed.io documentation site, built with Eleventy.

You need Node.js 20 or newer. From docs/:

npm install
npm run serve

Then open http://localhost:8080/.

npm run build

Output goes to docs/_site/.

• Templates use Liquid (same syntax as the previous Jekyll setup).
• Markdown is rendered by markdown-it with a small kramdown-IAL shim (docs/_lib/kramdown-block-attrs.js) so the existing {: .class} / {:toc} / {:.no_toc} syntax keeps working.
• Posts live in _posts/ (filename YYYY-MM-DD-<slug>.md); their permalinks come from _posts/_posts.11tydata.js.
• HTML output is minified by html-minifier-terser. CSS is gathered via Eleventy's addBundle('css'), minified with Lightning CSS, and inlined into <style>.
• Code blocks are syntax-highlighted at build time with Prism via @11ty/eleventy-plugin-syntaxhighlight — no client-side JS for highlighting.
• <img> elements pointing at local images are rewritten to <picture> with AVIF + WebP + original-format sources by @11ty/eleventy-img. Optimised assets land in _site/img/_optimized/.

The first production build takes ~60 s because it processes ~600 images. Local rebuilds use the cached output and finish in ~2 s.