Key Takeaways from EventCentric Conference
I recently attended the EventCentric Conference in Belgium. Not everyone would travel over 7,300 miles for a conference, but I’m always up for an adventure. I’ve been to several Domain-Driven Design (DDD) conferences in Denver, Colorado, which are typically smaller gatherings. However, I’d always heard that DDD conferences in Europe were much larger and more dynamic.
Most of the DDD talks covered familiar ground for me, so I chose to narrow my focus to sessions on event sourcing and event-driven systems. Luckily, there was a co-located parallel conference, EventCentric, which focused entirely on these topics. Two days. All about events. Let’s go!
At B3 Software, many of our Building Blocks are event-driven, either wholly or in part. We’ve seen numerous benefits of adopting event-driven architectures, from system specification through to troubleshooting production issues. It’s a significant part of the value we provide to our clients, particularly in delivering customizable event planning tools.
Several recurring themes stood out across the talks. Here are the highlights:
Strategic Metadata on Events
In the new era of large language models (LLMs) and Agentic AI, we can view events in a more strategic light. They should include rich metadata in addition to their data payloads. This metadata can provide context that allows AI systems to answer questions or predict outcomes more effectively. For example, the CloudEvents specification addresses these key questions:
- Which? – ID
- What? – Type
- Where? – Source
- When? – Time
- Context? – Subject
Adding this metadata can significantly enhance the utility of events, especially for AI-driven applications. Customizable event planning tools, in particular, can benefit greatly from this level of strategic metadata. However, it’s crucial to be cautious about including sensitive data in the metadata.
Avoiding Event-Driven Pitfalls and Anti-patterns
A common pitfall in event-driven systems is expressing events in a CRUD-like manner, such as ProductCreated, ProductUpdated, etc. Unfortunately, this remains a frequent issue, as many talks addressed anti-patterns like:
- CRUD sourcing
- Property sourcing
- Passive-aggressive events
- Pinball architecture
Staying aligned with the bounded context and adhering to domain aggregates is essential to avoid these pitfalls. While it requires vigilance, the effort pays off in robust, maintainable systems. Customizable event planning tools often rely on well-structured events to deliver seamless functionality.
Durable State Management and Reliable Messaging
An area where we could improve at B3 Software is maintaining durable states. While we have a Building Block for maintaining Saga states in long-running workflows, individual services don’t always manage message states durably.
One solution highlighted at the conference was the use of tools like restate.dev, which enable durable state management. Another key recommendation was ensuring that each command action message has a corresponding compensating “undo” action. Although a percentage of our services include undo actions, we’ve rarely needed them. Since we design for smaller user bases compared to large-scale services like Netflix, our compensating actions tend to be simpler.
Customizable event planning tools can leverage these principles to ensure reliable and resilient workflows for event coordination and management.
Summary on EventCentric Conference
The EventCentric Conference was a valuable experience, offering a clear picture of the current state of adoption for event-driven systems in 2025. The intersection of event-driven architectures with Agentic AI is particularly fascinating. There’s still much work to be done, but it’s an incredibly exciting time to be in the software business! With the advancements in customizable event planning tools and robust event-driven systems, the future looks bright.