That depends a lot on the scope of your implementation. For example do you want to use a single machine for storage or do you want to have a cluster of storage nodes? Also, if it’s e.g. a server implementation for usage within an organization, how much data do you want to store and how big will single objects be?
The implementation I’m writing is for a single machine. And it’s more like playing around with remoteStorage. But being able to store music would be kind of cool
Well, then you can use anything that’s comfortable for you. Filesystem, Redis, MongoDB, a SQL database, whatever you’re familiar with. Also, if you want to play around with it, maybe choose something you’re familiar with inspecting, so you can easily see what’s going on.