How Discord Stores Trillions of Messages

Discord initially used Cassandra to store its rapidly growing number of messages but faced significant performance issues as the database scaled. After experimenting with and seeing improvements, Discord decided to switch to ScyllaDB. This new database, written in C++, offered better performance and reduced maintenance complexity, addressing many issues encountered with Cassandra. To manage traffic spikes and improve read efficiency, Discord also implemented intermediary data services using Rust, which allowed for safer and more efficient concurrency. The transition has significantly enhanced performance and stability, enabling Discord to handle trillions of messages reliably.