Welcome
What will you learn in this course?
Who is the course for and prerequisites
Deep Dive: Event Sourcing in .NET
Deep dive into production-ready Event Sourcing in .NET
About This Course
Event Sourcing is a foundational design pattern in persistence architecture, frequently discussed in
conjunction with CQRS and DDD. It revolves around the concept of capturing the events that lead to the
current state instead of just storing the state itself, as traditionally done in CRUD systems with
normalized databases. This approach operates on the premise that the current state can always be
reconstructed from the sequence of events, but not the reverse.
In our Deep Dive course, we will explore Event Sourcing in greater detail, utilizing the Marten
library to implement a robust, production-ready event sourcing system. This course aims to provide a
thorough understanding of the principles and patterns of Event Sourcing, diving deeper into its integration with CQRS architecture.
By leveraging Marten, you will gain practical experience in building an application that effectively
captures and processes events, showcasing how to create a powerful and flexible data management solution.
Throughout the course, we will demystify the process of implementing event sourcing, enabling you to
understand and utilize its capabilities fully.
By the end of this Deep Dive course, you will have a comprehensive understanding of Event Sourcing,
its intricate relationship with CQRS architecture, and the tools you need to implement it successfully in a production environment.
Course Curriculum
4h 45m 9 sections
Chapter introduction
Setting up PostgreSQL
What is Marten?
A quick refresher of our domain
Writing some events to a stream
Applying events to an aggregate
Projecting events
Where will Marten fit into our CQRS architecture?
Recap
Outline of our plan
Making the command handlers work
A disclaimer on abstractions
Marten's test strategy
Making our unit tests work again
Using Marten's projection system
Using subscriptions for our UI
Solution cleanup
Recap
What you should try to avoid
Is it really the same event?
Making non-breaking changes
Contract-breaking changes
Writing new streams
Recap
Introduction
Where & When do projections run?
Single Stream Projections
Multi-Stream Projections
Testing Projections
Recap
Why do we need more info?
A quick refactor
Logging commands
Adding event metadata
Recap
Why do we need snapshots?
Marten's built-in snapshots
Dealing with concurrency issues
Custom snapshots
Recap
Integration scenarios
Event Subscriptions
The Saga Pattern
Recap
Further resources
Conclusion
Meet Your Instructor
Hannes Lowette
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