Amazon has launched a database that's compatible with the MongoDB API, but doesn't use any MongoDB code. The move is being seen as a counter-move to MongoDB's attempt to make Amazon pay up for using its open source software.
From a purely technical viewpoint, the news is that Amazon is changing to use its own DocumentDB rather than MongoDB. Amazon describes DocumentDB as:
“a fast, scalable, and fully managed document database service that supports MongoDB workloads... it is designed to be compatible with your existing MongoDB applications and tools.”
The rationale given by Amazon is that customers find it challenging to build performant, highly available applications on MongoDB that can quickly scale to multiple Terabytes because of the complexity that comes with setting up and managing MongoDB clusters. Amazon DocumentDB implements the Apache 2.0 open source MongoDB 3.6 API by emulating the responses that a MongoDB client expects from a MongoDB server, allowing customers to use their existing MongoDB drivers and tools with Amazon DocumentDB.
However, there's a lot that's not included in that view of the situation. Amazon and AWS has in the past been criticized for taking open-source software, doing some work on it then rebranding it without necessarily playing fair with the original developers. The thinking seemed to be that just having Amazon using your software was enough of a reward.
MongoDB obviously felt it was a big enough brand in its own right to try to avoid this type of behavior. It recently changed its license terms to explicitly say that if a company wanted to reuse and rebadge its database, explicity to offer MongoDB as a service, either needs to buy a commercial license or to open source the service.
At the time, Eliot Horowitz, CTO of MongoDB, said in a statement that:
“The market is increasingly consuming software as a service, creating an incredible opportunity to foster a new wave of great open source server-side software. Unfortunately, once an open source project becomes interesting, it is too easy for cloud vendors who have not developed the software to capture all of the value but contribute nothing back to the community. We have greatly contributed to — and benefited from — open source and we are in a unique position to lead on an issue impacting many organizations. We hope this will help inspire more projects and protect open source innovation.”
Which is a great challenge, but the outcome has been that Amazon just moved on. MongoDB's reaction hasn't quite been at the 'ya boo sucks' level, but they say that the API version that DocumentDB is compatible with out of date as it's two years old and lacking the important new features sucg as ACID transactions, global clusters and mobile synchronization.
In a not-very-hidden retort to the news, Dev Ittycheria, CEO of MongoDB, tweeted:
First they ignore you,
then they laugh at you,
then they try to copy you,
And then you change the world.
The hard-headed business market has taken a slightly more pessimistic view, with MongoDB shares closing 13% down at the close of the first day of trading after the Amazon announcement. It will be interesting to see what happens longer term; MongDB has a lot of developer fans, and the wider open-source community is unlikely to look well on Amazon's move.
