Atomic CSS that cannot be overridden, served from the edge.

Purser compiles this page's styles into one deterministic stylesheet; HypDriv builds it inside next build, proves every prerendered class exists, preloads it with Early Hints and pins your theme before the first byte reaches the browser.

Flashless themes

The theme stage reads the hyp_theme cookie or Sec-CH-Prefers-* hints and sets the classes on html at the edge.

Unstyled-atom guard

A build whose HTML references an atom missing from the stylesheet fails instead of shipping unstyled markup.

Zero-override audit

hypdriv audit css loads every route in headless Chrome at three widths, both themes, hover and focus.

Strict CSP

Static pages get a hash-based policy that includes the theme fallback script; dynamic pages get a nonce.