"Your standard database toolkit will tempt you to reach for a familiar abstraction layer: transactional isolation. If you can ensure that only one process can access the B-Tree at any time, then you don't have to worry about writes altering the data-structure while reads are in progress.
Homey don't play that: transactions are a form of locking, and I un-friended locking years ago, for posting too many lame updates to my log files."