Is there something like SQLite, but document-oriented?

Question

Database

A C++/Qt program Needs to store a small but very cleverly organized dataset, and ensure multiple local applications run simultaneously. Before me, the issue was solved by SQLite, but now with new additions to the dataset, this will generally be the finish line.
Tell the lib to work locally, like SQLite, but the workflow was more like MongoDB. And simultaneous read access, albeit with sequential write., would be very desirable.

Answer 1

Lots of results on google. For example, https://unqlite.org