Infrastructure
What Mod_PageSpeed taught us about modern web performance
Years ago, we used Mod_PageSpeed because it automated a lot of repetitive front-end optimization at the server. The tools changed. The lesson did not: performance is a system, not a button.
Automating optimization was the right instinct
Mod_PageSpeed could rewrite images, CSS, JavaScript, caching behavior, and other delivery details automatically. At the time, that was useful because it made good performance habits more consistent across sites that were otherwise easy to neglect.
The durable lesson was not that one module should control every optimization. It was that repeatable performance work belongs in the system instead of depending on someone remembering a checklist before launch.
The web stack moved on
Modern delivery has more capable protocols, Brotli compression, responsive images, WebP and AVIF, native lazy loading, CDNs, edge caching, and better build and deployment tooling. Many jobs that once justified a server-side rewrite layer now belong closer to the asset pipeline, application, browser, or edge.
That does not mean every new feature should be turned on. The useful question is still the same: what removes real work for the browser, origin, or visitor without making the system harder to operate?
Measure the origin, not just the output
A fast-looking cache hit can hide a slow origin. Database queries, PHP runtime, object caching, scheduled jobs, plugin behavior, third-party calls, and available compute all affect how quickly useful HTML can be produced and how reliably the site behaves under load.
Use lab tests to reproduce a problem, field data to understand real visitors, and server-side measurements to find work that browser scores cannot see. Performance work gets better when the measurement matches the layer being changed.
Keep the lesson, retire the dependency
Our current approach is deliberate rather than magical: optimize media at ingestion, cache at the correct layer, keep third-party JavaScript on a short leash, use modern transport and compression, protect the origin, and monitor representative pages after meaningful changes.
Mod_PageSpeed is part of our history, not our current default. The lesson worth keeping is that speed is an operating standard shared by content, development, hosting, and maintenance.