About this guestbook

It's the guestbook from Fourfold's design notes, and it shows M4's pieces:

Templates with fields. index.html has fields like {{count}}, filled by render in index.ms. Every value is escaped for where it goes.
Fragments. Each entry is frags/entry.html, rendered once per item with frag("entry", list), and again on its own when someone signs.
Includes. The header is frags/header.html, pasted into each page with {{> header}}.
Markdown. Messages go through markdown(), as Limited Markdown (the default): no images, no headings, and javascript: links come out as plain text. This page is Markdown too, in frags/layout/markdown.html, and is also served as Markdown, at /about.md.
HTMX. The form posts with hx-post, and the new entry is swapped in without a reload. Without JavaScript, the same handler redirects back.