The engine was created from scratch. It can do JOINs but hasn't yet implemented all the different kinds of joins.
It is a completely different architecture (originally designed to be a file system replacement where multiple tags could be attached to each and every file) and the database functionality was almost discovered by accident. The tags I invented to make finding files based on them extremely fast, looked a lot like a columnar store. So I tried building regular relation tables using them. It surprised me when queries against my tables gave other databases (with decades of development behind them) a real run for their money.
It is a completely different architecture (originally designed to be a file system replacement where multiple tags could be attached to each and every file) and the database functionality was almost discovered by accident. The tags I invented to make finding files based on them extremely fast, looked a lot like a columnar store. So I tried building regular relation tables using them. It surprised me when queries against my tables gave other databases (with decades of development behind them) a real run for their money.