After one year in development we launched in 2026 🥳
Powerfull
Caching Features
Queue-based preloading
Batch controls, concurrency, retry tracking, stop/resume, ETA, and WP-CLI support for automation.
Built-in diagnostics
Cache coverage, hit/miss stats, response timing, system environment, object cache status, and DB footprint.
Asset versioning
Safe CSS/JS cache busting via mtime query keys. Optional Cloudflare static asset rule deployment.
Image optimization
Client-side compression and conversion with visible savings indicators — no external processing services.
Selective invalidation
Purge hooks for posts, comments, menus, terms, updates, and Woo stock — with warm cache options.
Premium admin experience
Status indicators in posts and Media Library, curated settings, and optional “kill bloat” tools.
Works locally and at the edge
Speed of Light serves cached HTML directly from your server, and optionally pushes the same cache to Cloudflare’s edge. You can verify both — directly from response headers.
Edge Cache
Cloudflare Edge
Speed of Light writes a static HTML file to disk and on future requests serves that file before WordPress boots. If Cloudflare edge caching is enabled, SOL deploys cache rules and sends Cache‑Control headers (with s‑maxage) so Cloudflare knows which responses are cacheable and for how long. Cloudflare then fetches the already‑cached HTML from your server and stores it globally; subsequent visitors are served directly from the edge.
Local Cache
Speed of Light Engine
Full-page static HTML is written to disk on first render and then served directly from disk before WordPress bootstraps on subsequent anonymous GET requests, so PHP and MySQL are bypassed for cached pages. This delivers the fastest possible local response time without a CDN, while logged-in users, admin screens, carts/checkout, and other excluded URLs continue to run through WordPress normally.
The Difference
We don’t want to put others on blast but the truth is, other plugins either straight up lie about caching mechanisms or hide behind external server calls to hide “proprietary” methods.| Feature | Speed of Light | Typical Cache Plugins |
|---|---|---|
| Serves HTML before WordPress loads | Yes | No |
| Disk-based static HTML cache | Yes | Sometimes |
| Selective cache invalidation | Yes | Rarely |
| Warm cache publishing flow | Yes | No |
| Cloudflare edge caching (Free plan) | Yes | Often paid-only |
| Runs entirely on your server | Yes | Sometimes external |
| Transparent cache headers & stats | Yes | Limited |
| Client-side image optimization | Yes | Often separate plugin |
| Safe asset versioning (no rewriting) | Yes | Often rewrites |
| Hidden External Server Calls | No | Usually |
| Designed for power users | Yes | Mixed |