Congrats on your first NPM lib! Just briefly looked through.
Really good job on providing unit tests and you have documented all your code as well!
You should consolidate the README.md in the lib folder to the main README.md in root so that it's all up front and in one place.
Consider using changesets to manage your commit and publish workflow:
https://github.com/changesets/changesets
(An example changeset is like "chore: update packages" along with a wider description of the update)
I use changesets with some of my other projects if you want to see examples:
- https://github.com/theogravity/loglayer
- https://github.com/theogravity/datadog-transports (monorepo example)
What I like about it is it does all the work of creating the release / changelogs and also consolidating multiple changes into a single release as well. Also makes it easier for people to contribute to your project since it's a known standard.
