Mongo-Mock

Mongo-Mock (v4.2.0, last released 2022) is an in-memory mock implementation of the MongoDB server, designed to mimic the official MongoDB Node.js driver API. It allows developers to test MongoDB interactions without a real database, supporting basic CRUD operations, async simulation with configurable delay, optional disk persistence, and some query operators. Compared to alternatives like mongodb-memory-server, it is lighter-weight but has limited feature coverage and is no longer actively maintained.