Akka Persistence R2DBC


An implementation of the Akka Journal and Snapshot store persistence plugin APIs, and the full Persistence Query API with R2DBC. The plugin has a few additional extensions documented below.



The plugin provides the default settings as part of the reference.conf of the database flavour:

Unlike the other AsyncWriteJournal calls, the asyncReplayMessages one is not protected by a circuit-breaker, for a good reason:

This call is NOT protected with a circuit-breaker because it may take long time to replay all events. The plugin implementation itself must protect against an unresponsive backend store and make sure that the returned Future is completed with success or failure within reasonable time. It is not allowed to ignore completing the future.

The plugin guarantees that the Future is completed by imposing a time limit on the SQL stream's completion. You can configure the timeout with the replay-messages-timeout parameter, the default value is 10s (in line with the circuit breaker settings).


  • akka.serialization.AsyncSerializer support
  • Atomic Projections gives you the ability to persist an event and run projections for a "local" read-side in an atomic transaction.

Atomic Projections

The goal of the extension is to allow you to enjoy the benefits of CQRS and Event Sourcing without incurring the costs of running a more complex infrastructure for those cases when you really don't have to.


Contributions via GitHub pull requests are gladly accepted from their original author. Along with any pull requests, please state that the contribution is your original work and that you license the work to the project under the project’s open source license. Whether you state this explicitly, by submitting any copyrighted material via pull request, email, or other means you agree to license the material under the project’s open source license and warrant that you have the legal authority to do so.


This project is licensed under the Apache 2.0 license.