Commanded

Use Commanded to build your own Elixir applications following the CQRS/ES pattern.

Provides support for:

• Command registration and dispatch.
• Hosting and delegation to aggregates.
• Event handling.
• Long running process managers.

Commanded provides a solid technical foundation for you to build on. It allows you to focus on modelling your domain, the most important part of your app, creating a better application at a faster pace.

You can use Commanded with one of the following event stores for persistence:

• EventStore Elixir library, using PostgreSQL for persistence
• Greg Young's Event Store.

Please refer to the CHANGELOG for features, bug fixes, and any upgrade advice included for each release.

---

• Changelog
• Wiki
• Frequently asked questions
• Getting help

MIT License

---

Overview

• Getting started
• Choosing an event store
  • PostgreSQL-based EventStore
  • Greg Young's Event Store
• Using Commanded
  • Aggregates
    • Example aggregate
    • Commanded.Aggregate.Multi
    • Aggregate state snapshots
  • Commands
    • Command handlers
    • Command dispatch and routing
      • Define aggregate identity
      • Multi-command registration
      • Dispatch timeouts
      • Dispatch consistency guarantee
      • Dispatch returning execution result
      • Aggregate lifespan
      • Composite command routers
    • Middleware
      • Example middleware
  • Events
    • Domain events
    • Event handlers
      • Consistency guarantee
  • Process managers
    • Example process manager
  • Supervision
  • Serialization
  • Read model projections
• Deployment
  • Single node deployment
  • Multi node cluster deployment
  • Multi node, but not clustered deployment
• Testing with Commanded
• Used in production?
• Example application
• Learn Commanded in 20 minutes
• Event store provider
• Contributing
• Need help?

---

Used in production?

Yes, Commanded is being used in production.

• Case Study: Building a CQRS/ES web application in Elixir using Phoenix

Example application

Conduit is an open source, example Phoenix 1.3 web application implementing the CQRS/ES pattern in Elixir. It was built to demonstrate the implementation of Commanded in an Elixir application for the Building Conduit book.

Learn Commanded in 20 minutes

Watch Bernardo Amorim introduce CQRS and event sourcing at Code Beam SF 2018. Including a tutorial on how to implement an Elixir application using these concepts with Commanded.

Contributing

Pull requests to contribute new or improved features, and extend documentation are most welcome.

Please follow the existing coding conventions, or refer to the Elixir style guide.

You should include unit tests to cover any changes. Run mix test to execute the test suite.

Contributors

• Andrey Akulov
• Andrzej Sliwa
• Ben Smith
• Bernardo Amorim
• Brenton Annan
• Chris Brodt
• David Carlin
• Florian Ebeling
• Henry Hazan
• Joan Zapata
• Kok J Sam
• Leif Gensert
• Luís Ferreira
• Olafur Arason
• Patrick Detlefsen
• Raphaël Lustin

Need help?

Please open an issue if you encounter a problem, or need assistance. You can also seek help in the Gitter chat room for Commanded.

For commercial support, and consultancy, please contact Ben Smith.