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 aggregate roots.
• Event handling.
• Long running process managers.

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.

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• Changelog
• Wiki
• Frequently asked questions
• Getting help

MIT License

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Overview

• Getting started
• Choosing an event store
  • PostgreSQL-based EventStore
  • Greg Young's Event Store
• Using Commanded
  • Aggregate roots
    • Example aggregate root
    • Commanded.Aggregate.Multi
  • Commands
    • Command handlers
    • Command dispatch and routing
      • Define aggregate identity
      • Multi-command registration
      • Dispatch timeouts
      • Dispatch consistency guarantee
      • Dispatch returning execution result
      • Aggregate lifespan
    • Middleware
      • Example middleware
  • Events
    • Domain events
    • Event handlers
      • Consistency guarantee
  • Process managers
    • Example process manager
  • Supervision
  • Serialization
  • Read model projections
• Used in production?
• Example application
• Limitations
• Event store provider
• Contributing
• Need help?

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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.

Limitations

Commanded is currently limited to running on a single node. Support for running on a cluster of nodes (#39) is under active development.

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
• Brenton Annan
• Olafur Arason
• Chris Brodt
• David Carlin
• Patrick Detlefsen
• Florian Ebeling
• Leif Gensert
• Henry Hazan
• Raphaël Lustin
• Kok J Sam
• Andrzej Sliwa
• Joan Zapata

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.