how to cache high-traffic read-heavy apis, like when youre typing on your phone

we're building a new api that's expected to have a massive amount of reads but very few writes. think real-time analytics dashboards. we're considering a multi-layered caching approach, maybe redis for hot data and memcached for slightly colder data, backed by a cdn for static content. what are your go-to strategies for these kinds of scenarios? any specific patterns or pitfalls to watch out for when dealing with such high read volumes and ensuring cache coherence