WCKD Fast Pages is a deliberately small full-page cache for sites without a
logged-in front end (brochure sites, organizations, portfolios). The first
visit to a page saves its finished HTML; every visit after that is served
straight from disk before WordPress or the database load, typically
20 to 30 times faster server response.

Built to be boring:

Content edits clear the cache automatically, so visitors never see stale pages. Editing a page clears just that page and the listings that show it, then rebuilds them in the background.
Visitors arriving through ads and email links (utm tags, click ids) get the instant copy too. Tracking is untouched: it runs in the browser.
Each page is compressed once when saved, so browsers get a ready-made gzip copy and the server never compresses the same page twice.
Logged-in users, visitors with a shopping cart in progress, previews, real query strings, search, feeds, and POST requests always bypass. A page a plugin marks as private is never saved.
Security headers a plugin adds, such as a Content-Security-Policy, are sent with saved pages too.
Deactivating, deleting, half-removing or half-uploading the plugin can never break the site: every failure path falls through to a normal WordPress render.

The dashboard (Settings Fast Pages):

A measured, plain-language speed banner (“Pages on this site load 22× faster…”) with one-click re-measuring.
Every page on the site with its cache status, timestamp and size, 50 at a time, with filters and search, plus per-page refresh.
A “Cache All” button that rebuilds every page’s saved copy, one page at a time. Each row updates live as its page is cached, with a time estimate, Pause, Resume and Stop.
Pause serving for one hour (auto-resumes).
Settings for what to always show live (content types, categories, tags or specific addresses), how much to clear after an edit, and how fast Cache All runs.

Technical notes (for hosts and developers): on activation the plugin
installs a wp-content/advanced-cache.php drop-in and defines WP_CACHE
in wp-config.php, the standard mechanism that lets cached pages skip
WordPress entirely. It never overwrites another plugin’s drop-in, and
deactivation/uninstall remove both cleanly. Respects DONOTCACHEPAGE and
Cache-Control: private or no-store, offers filters for what is saved,
what bypasses and what an edit clears, and honours the
WCKD_FAST_PAGES_DISABLED and WCKD_FAST_PAGES_TTL constants. WP-CLI:
wp fast-pages status | purge | warm.