Pretty much every application has state, the bigger your application the more state you have. Things can get challenging when you are asking much of your state. You might need to maintain multiple indexes into your state, react to changes to the state, keep multiple pieces of state in sync and make sure that all of it is thread-safe for multiple readers and writers. Doing this for one piece of state is a challenge, but doing it for a few dozen is painful.

Presenting, StateDB (cilium/statedb) a non-persistant in-memory database of your application state. It was created to tackle state management challenges experienced by Cilium. It leverages Go features such as generics, iterators, channels and Go’s garbage in combination with immutable data structures to make complex state management easy.

StateDB provides Multi Version Concurrency Control (MVCC) through snapshots, indexing(multiple indexes per table, unique and non-unique indexes, composite keys), write transactions across multiple tables and the ability to watch for changes on a whole table or a subset of data. To name a few.

Let's explore StateDB together and take a little peek under the hood.