TingoDB

TingoDB is an embedded JavaScript database for Node.js, designed to be upwardly compatible with MongoDB's v1.4 API. It can operate either as an in-process filesystem database, storing data on disk, or entirely in memory. While the npm metadata shows version 0.6.1 and a README excerpt mentions an `apiLevel` parameter in 0.6.x for some 2.x specific behaviors, the project appears to be largely abandoned, with the last update noted in 2015/2018 and the author explicitly stating its abandonment in 2019. Its key differentiator was offering a local, file-based or in-memory data store with a familiar MongoDB-like query interface, rigorously tested using portions of the official MongoDB Node.js driver's test suite, allowing it to potentially serve as a drop-in replacement for applications built against older MongoDB driver versions.