Architecture & ModernizationConference50min
Taming Microservice Overload: Our Journey to Modular Monoliths
At the Port of Rotterdam, an overgrown microservices architecture created operational complexity and fragmented ownership. This talk shows how Domain-Driven Design and Spring Modulith were used to consolidate services into modular monoliths, preserving domain boundaries while improving maintainability, clarity, and team ownership.
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Mario KlaverPort of Rotterdam
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Thursday, October 8, 11:50-12:40
TBA 4
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At the Port of Rotterdam, our system had grown into far more microservices than our teams could effectively own. The result: operational overhead, fragmented domain knowledge, and an overgrown architecture that was hard to maintain and evolve.
In this session, I’ll share how we combined Domain-Driven Design (DDD) with Spring Modulith to consolidate our microservices into a smaller set of modular monoliths. Each microservice represents a bounded context, with modules organized around distinct business capabilities, preserving clear domain boundaries while reducing operational complexity.
You’ll learn:
If your microservices landscape has outgrown your teams, this talk shows how modular monoliths can restore clarity, ownership, and long-term maintainability, without compromising architectural integrity.
In this session, I’ll share how we combined Domain-Driven Design (DDD) with Spring Modulith to consolidate our microservices into a smaller set of modular monoliths. Each microservice represents a bounded context, with modules organized around distinct business capabilities, preserving clear domain boundaries while reducing operational complexity.
You’ll learn:
- How to define and model business domains and bounded contexts using DDD
- How to implement these domains as modular monoliths with Spring Modulith
- How Spring Modulith keeps your modules clean and maintainable
- Common pitfalls we encountered and how we solved them
If your microservices landscape has outgrown your teams, this talk shows how modular monoliths can restore clarity, ownership, and long-term maintainability, without compromising architectural integrity.
Mario Klaver
Mario Klaver is a Solution Architect at the Port of Rotterdam, where he is responsible for the digital systems supporting Harbour Master operations. With a background in Java and Kotlin development, he focuses on building clean, modular software architectures for mission-critical environments. Combining hands-on engineering experience with a pragmatic approach to architecture, Mario Klaver helps teams design systems that are scalable, understandable, and built to last — even under 24/7 operational demands.