DocumentDB 1.0 is the first generally available release of the open source, MIT-licensed document database built on PostgreSQL, with compatibility for the MongoDB wire protocol. Most MongoDB drivers, tools, and queries work without changes.
DocumentDB consists of a PostgreSQL extension that provides MongoDB API-compatible functionality and a gateway that translates MongoDB protocol requests into PostgreSQL calls. Version 1.0 supports PostgreSQL 15–18 through container images, with Linux packages available for PostgreSQL 17 and 18, and includes a Kubernetes operator, with the GA focusing on security, stability, and fixes for indexing, aggregation, and geospatial queries.
Microsoft announced the open source project early in 2025, aiming to provide the developer community with a NoSQL datastore built on PostgreSQL, and offering full visibility into the engine's architecture and implementation. The project joined the Linux Foundation a few months later, with support from other large database organizations including AWS, Cockroach Labs, Google, Snowflake, and Yugabyte. In the recent article "DocumentDB and the MIT License: What to Know Before You Build, Deploy, and Distribute," the team explains how DocumentDB’s permissive MIT license allows commercial use, modification, and hosting without requiring disclosure of proprietary code, contrasting it with MongoDB’s SSPL.
Even if the project provides a page discussing the DocumentDB name disambiguation, covering the open source project, Azure DocumentDB, and Azure Cosmos DB, the community remains perplexed about the choice. In a popular Hacker News thread, user marifjeren writes:
Name it anything else for god's sake. DocumentDB is already what everybody calls Amazon DocumentDB.
With multiple open source options now on the market, Patty Chow, product manager at Microsoft, explains why open-source document databases need multiple implementations to give developers more choice in deployment and infrastructure while preserving compatibility with MongoDB drivers and queries. Chow writes:
MongoDB has given developers a widely used way to work with document data. Familiar drivers and query patterns are worth preserving. Alternative implementations give developers a chance to keep using that knowledge while evaluating different approaches to storage and deployment.
In a Reddit thread, some practitioners raise concerns about current MongoDB compatibility and confusion with similarly named products. User 716green comments:
Compatibility between MongoDB and FerretDB has been absolutely minimal compared to what you would probably expect. I've been a fan of DocumentDB for a long time and I love that Microsoft is supporting FerretDB.
DocumentDB provides the PostgreSQL extensions and its own MongoDB-compatible gateway, while FerretDB is a separate project that uses the DocumentDB extensions as its backend and provides its own MongoDB-compatible interface.
Layerbase recently ran an initial comparison of FerretDB and the PostgreSQL-based DocumentDB using YCSB benchmarks, finding that DocumentDB delivered 20–33% higher read throughput, while FerretDB had lower tail latency for updates in mixed workloads, but noting the results are not conclusive. An open GitHub issue reports higher query latency in DocumentDB 1.0 than MongoDB 9.0.4 across several workloads, but the results have not been independently verified.
The DocumentDB release notes include upgrade paths and known issues. The project plans separate long-term support and development tracks, with its versioning policy still under discussion.