They discuss different caching APIs, transparent caching layers, cache keys and surrogate keys, SSG as a high-level caching solution, Next.js 13.2's cache API, Russian doll caching in Rails, fetch cache abstraction, retro on using Hygraph as Build UI's CMS, and caching challenges in a serverless setup.
Caching CMS data can improve performance by reducing reliance on runtime services and eliminating unnecessary service calls.
The Next.js cache and its ability to cache fetch calls at the page and fetch level can lead to faster page loading times and reduced reliance on runtime services.
Caching specific sub-trees of a component tree based on surrogate keys can improve performance by eliminating unnecessary work and caching only relevant parts of the page.
Deep dives
Cache Management and CMS Retro
The podcast hosts discuss their experiences with a content management system (CMS) and the benefits and drawbacks they encountered. They mentioned using a CMS for storing their content library, emphasizing the importance of being able to cache CMS data to improve performance. They also highlight the challenge of eventual consistency when using a CMS, as changes made to the content take some time to reflect in the cached data. Additionally, they discuss the trade-offs between using a CMS and building custom admin interfaces, noting the advantages of a CMS's UI and environment-independent data.
Next.js Cache and Fetch Caching
The podcast hosts mention the Next.js cache and its ability to cache fetch calls at the page and fetch level. They speculate on the potential benefits of this feature, including faster page loading times and reduced reliance on runtime services. They discuss the idea of having a fetch cache that allows for revalidation based on specified time limits or programmatic triggers. They also touch on the idea of using surrogate keys to associate cache entries with specific fetch calls and the potential to automatically evict cache entries based on changes in the backend data.
Caching Strategies and Future Considerations
The hosts explore different caching strategies and future considerations for optimizing performance. They discuss the importance of caching data from runtime services such as CMS and Stripe, highlighting the potential benefits of eliminating unnecessary service calls and reducing request times. They mention the potential challenges of caching dynamic data and the need to revalidate and update cached content as changes occur. They also touch on the idea of shared memory storage, such as Redis, for efficient caching and how it could be a valuable component in building a robust caching system.
Using surrogate keys and caching in component trees
The concept of surrogate keys and caching with keys is discussed, specifically in the context of component trees. The idea is to break down a component tree into sub-trees and cache specific sub-trees that depend on certain keys. For example, in a Rails application, the homepage can be cached based on the videos published in the CMS, while the header portion can remain dynamic. This allows for shared work to be done once and improves performance.
Different levels of caching and abstracting data fetching
The episode explores different levels of caching and how data fetching can be abstracted away for better developer experience. The discussion revolves around different layers, such as Redis as a low-level cache, caching at the component level, and even caching queries and results. The goal is to eliminate unnecessary IO operations and prevent the need for manual eviction of cache entries. The concept of tying database queries to component rendering is also highlighted as a potential approach for better data caching and fetching.
Sam and Ryan have an open-ended conversation about different caching APIs and what kinds of benefits they might afford app developers. They discuss transparent caching layers, cache keys and surrogate keys in systems like Fastly, how SSG is effectively a high-level caching solution, Next.js 13.2’s cache API, Russian doll caching in Rails, whether a fetch cache is too high-level of an abstraction, and other topics.
They also have a retro on choosing to use Hygraph as Build UI’s CMS, discussing some surprises they encountered including the fact that Hygraph favors high availability over consistency (stale reads, which can cause issues with serverless) and rate limits (which causes issues with SSG).
