caching

ETags are a simple high-impact performance lever: they reduce bandwidth and controller CPU. Use stale? with a stable ETag component list and last_modified so intermediary caches and browsers can do conditional GET.

When cache structures change, you want to invalidate safely without flushing the world. Use a namespace version key (per feature) and incorporate it into cache keys.

Turbo Frames can trigger lots of small requests, so caching matters. For expensive frame endpoints (like an activity panel), I use stale? with an ETag that includes a cache key and the latest update timestamp. If the content hasn’t changed, Rails retu

I use Django's cache framework to avoid expensive queries and computations. The cache_page decorator caches entire view responses by URL. For more control, I use the low-level cache API to store query results or computed values. I set reasonable timeo

Glide efficiently loads and caches images from network, disk, or resources. I use Glide.with(context).load(url).into(imageView) for basic loading. Transformations apply effects—centerCrop(), circleCrop(), RoundedCorners(). Placeholders show during loa

I’ve had endpoints where the same lookups get repeated across helpers and partials, and I didn’t want to pay for query caching on every request. In Scoped query cache, I wrap only the expensive report build in ActiveRecord::Base.cache, so the cache li

Materialized views store query results physically for fast access. I use them for expensive aggregations, complex joins, reporting queries. Unlike views, materialized views cache data—need manual refresh. REFRESH MATERIALIZED VIEW updates cached data.

For read-heavy endpoints, clients often fetch the same resource repeatedly (profile data, settings, a snip page) even when it hasn’t changed. ETags let the client send If-None-Match and the server respond with 304 Not Modified, saving bandwidth and CP

Redis provides fast in-memory caching for Django. I configure it as cache backend and use for session storage. I cache expensive querysets, computed values, and API responses. The cache.get_or_set() method simplifies cache-aside pattern. For cache inv

Rails caching dramatically improves performance by avoiding expensive computations and queries. Fragment caching caches view partials. Russian doll caching nests cache fragments for efficient invalidation. Low-level caching stores arbitrary data. Rail

If a hot key expires, you can stampede your DB. race_condition_ttl lets one process recompute while others serve stale content briefly. This is a reliability pattern masquerading as caching.

Redis provides a fast, in-memory cache for expensive computations that don't change frequently. I use Rails.cache with the Redis store to cache things like trending posts calculations, aggregated statistics, or external API responses. The fetch method