ways to cache stuff for apis that get read a lot, you know

hey everyone, i'm working on a system with a really read-heavy API and we're looking at caching to improve performance. we've considered in-memory caching, but we're worried about scalability and consistency issues if we go distributed. what caching strategies are you all using for similar scenarios? are you using Redis, Memcached, or something else? how do you manage cache invalidation effectively without impacting read performance too much?