MongoDB Responds as AWS, Google, Microsoft Back Open Source Alternative
'Why do we hear so much about Postgres adoption?' asked one analyst.
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CEO Dev Ittycheria had just given his overview on “another strong quarter” when a financial analyst on MongoDB’s Q2 FY2026 earnings call asked about two new sources of competition.
One, Databricks’ Lakebase database. And two, DocumentDB, an open source database that has gained the backing of AWS, Google Cloud, Microsoft, Snowflake, and a half-dozen other data & AI players.
“How might they impact MongoDB?” the analyst asked. “And how do you differentiate?”
Databricks ‘threw in the towel’
The timing and juxtaposition of these three points of reference are notable. In the span of seven days, Databricks disclosed (on Aug. 19) plans to invest in the development of Lakebase, the Linux Foundation revealed (on Aug. 25) that it is taking on DocumentDB as an open source project, and MongoDB announced (on Aug. 26) a 24% year-over-year increase in Q2 revenue, to $591 million. Mongo’s stock price spiked on the earnings results.
TLDR: MongoDB is under increasing pressure from industry heavyweights even as its database business is growing robustly.
Ittycheria was ready for the hard questions. Databricks, he replied, had started down the path of developing its own online transaction processing (OLTP) database only to discover it was a non-trivial undertaking. Instead, Databricks “threw in the towel” and acquired Neon and its OLTP database. “It just reinforces that OLTP is the strategic high ground for AI,” he added.
What about Postgres?
On the question of industry support for the open source DocumentDB database—now, a more viable alternative to MongoDB—Ittycheria responded that “the hyperscalers are investing less and really handing off to the open-source community to kind of really take on the bulk of the work in terms of product development.”
In other words, according to that POV, three of the top four database companies (Oracle being the exception) are actually making a lesser commitment to DocumentDB by leaving the heavy lifting to others.
Here I should point out that the Linux Foundation-backed DocumentDB is a PostgreSQL database with a MongoDB API. Depending on your point of view, that’s either a best of both worlds design (Postgres + MongoDB compatibility) or a Frankenstein approach. [Oracle has its own MongoDB API, which I’ve written about previously.]
MongoDB is a NoSQL document database, and Postgres is a SQL relational database. They are fundamentally different models, each with its own advantages.
“Why do we hear so much about Postgres adoption for AI startups?” the financial analyst asked next.
“Good question,” said Ittycheria. “What’s become clear is a lot of these startup founders don’t think that hard about their database choice. They kinda go with what they know. And what we are seeing is that as some of these startups are scaling, they’re running into real scaling challenges with Postgres.”
That explanation, I’m sorry to say, sounds a bit like blaming the startup teams that MongoDB hopes eventually to convert into customers. And it raises the question of which platform is actually more scalable—MongoDB or Postgres?
The answer is it depends, as you can see from the AI response below.
The scalability question
I asked Anthropic’s Claude: “How do Postgres and MongoDB compare in terms of enterprise scalability?” Here’s what Claude said:
- begin AI response -
Real-World Enterprise Usage
PostgreSQL: Used by companies like Apple, Instagram, and Spotify for core transactional systems
MongoDB: Powers applications at Facebook, Adobe, and eBay for content management and real-time analytics
Bottom Line PostgreSQL offers more predictable, mature enterprise scalability with strong consistency guarantees. MongoDB provides more flexible, automatic horizontal scaling but with eventual consistency trade-offs. The choice often depends on your specific data model, consistency requirements, and growth patterns rather than pure scalability metrics.
- end AI response -
I don’t consider Claude to be the ultimate authority on database scalability, but as a gut-check it undermines Ittycheria’s contention that Postgres pales in comparison to MongoDB.
To be continued…
The competition between MongoDB and Databricks, and between MongoDB and DocumentDB, isn’t a zero-sum game. It’s possible, even probable, that all three platforms will keep growing. It’s just that some growth will come at the expense of other growth.
And it’s fair to say that MongoDB and the hyperscalers that are backing DocumentDB aren’t necessarily archenemies. MongoDB is available on AWS, Google Cloud, and Azure. “Our hyperscaler partnerships remain strong,” said Ittycheria.
Even so, the competitive landscape feels different today that it did a few weeks ago.
See the full transcript of MongoDB’s Q2 FY2026 earnings call here, courtesy of Motley Fool.
Further reading
“AWS joins the DocumentDB project to build interoperable, open source document database technology,” - AWS
