In the article, they say: >The service we switched from Go to Rust is the “Read States” service. Its sole purpose is to keep track of which channels and messag

In the article, they say: >The service we switched from Go to Rust is the “Read States” service. Its sole purpose is to keep track of which channels and messages you have read >On cache key eviction, we commit your Read States to the database. We also schedule a database commit for 30 seconds in the future whenever a Read State is updated. So it's a separate service whose only purpose is to store data in-memory with occasional commits to persisted DB, which sounded a lot like Redis. But of course, a special optimized service is always going to outperform a general purpose tool such as Redis. They also replaced HashMaps with BTreeMaps, reduced the number of memory copies they were doing, etc. -- which has nothing to do with Go, but also contributed to a performance increase