FerretDB

FerretDB is an open-source proxy that accepts MongoDB wire protocol connections and converts the queries to SQL. It stores data in PostgreSQL with the DocumentDB extension, and clients connect with any MongoDB driver. The project is written in Go and ships as a container image, a .deb package, a Kubernetes deployment and a Go library that embeds it in an application. The packages include a systemd unit that starts the server.

FerretDB Cloud is a managed service that runs FerretDB instances for you.

Worth knowing

The project’s homepage does not answer, so the record is a stub until a homepage is readable again or the project names a new one.