Hi! I wanted to understand more about databases' internals so I wrote one from scratch. It has a T-SQL inspired syntax with support for functions and procedures. It can be used stand-alone as a SQL engine or with a server allowing for persistence and replication to other connected clients.
Performance are nothing near sqlite of course but that's beside the point. It’s a small database engine that can run in a web app as a way to store session data, do small calculations on a web worker, store the document/data the user is editing or facilitate “multiplayer” feature by broadcasting the queries the web app is running. The server runs in a container for that specific document and shutdowns automatically after a set amount of minutes of inactivity.