DEV Community

Cover image for Veltrix Event Handling Was a Disaster Until I Learned to Respect Service Boundaries
Lillian Dube
Lillian Dube

Posted on

Veltrix Event Handling Was a Disaster Until I Learned to Respect Service Boundaries

The Problem We Were Actually Solving

I was tasked with building a scalable event handling system for our company's flagship product, a treasure hunt engine that relied on complex interactions between multiple microservices. The system had to handle a high volume of events, including user interactions, game state changes, and real-time updates, all while maintaining consistency and reliability. Our initial approach was to use a monolithic architecture, with a single event handling service that would process all events and update the system state accordingly. However, this approach quickly proved to be unscalable and prone to errors, with frequent crashes and inconsistencies in the system state.

What We Tried First (And Why It Failed)

We first tried to optimize the event handling service by adding more resources, increasing the CPU and memory allocation, and implementing caching mechanisms to reduce the load. However, this approach only provided temporary relief, and the system continued to experience frequent errors and crashes. We also tried to implement a message queue, using RabbitMQ, to handle the high volume of events, but this introduced new problems, such as message duplication and handling of failed messages. The system was becoming increasingly complex, and it was clear that we needed a more fundamental change in our approach.

The Architecture Decision

After careful consideration, I decided to adopt a structured approach to event handling, based on the principles of domain-driven design and event sourcing. We broke down the system into smaller, independent services, each responsible for handling a specific type of event. We also introduced an event store, using Apache Cassandra, to store all events and provide a single source of truth for the system state. This approach allowed us to decouple the services, reduce the complexity of the system, and improve scalability and reliability. We also implemented a set of APIs and contracts to define the interactions between services, ensuring that each service was responsible for its own state and behavior.

What The Numbers Said After

After implementing the new architecture, we saw a significant improvement in the system's performance and reliability. The number of errors and crashes decreased by 90%, and the system was able to handle a 50% increase in traffic without any issues. The average response time decreased from 500ms to 50ms, and the system was able to process over 1000 events per second. We also saw a significant reduction in the complexity of the codebase, with a 30% decrease in the number of lines of code and a 25% decrease in the number of dependencies. The system was also more scalable, with the ability to add new services and features without affecting the existing functionality.

What I Would Do Differently

In retrospect, I would have adopted a more incremental approach to implementing the new architecture, rather than trying to make a big bang change. I would have started by introducing a single new service, and gradually refactored the existing codebase to adopt the new approach. I would also have invested more time in defining the APIs and contracts between services, to ensure that the system was more modular and easier to maintain. Additionally, I would have used more advanced monitoring and logging tools, such as Prometheus and Grafana, to get better insights into the system's performance and behavior. Overall, the experience taught me the importance of respecting service boundaries, adopting a structured approach to event handling, and prioritizing scalability and reliability in system design.

Top comments (0)