Architecture, Perf. & Sec.Conference50min
Eventual Consistency: A Question of Time and Expectations
Cette présentation montre comment passer de flux synchrones fragiles à des architectures asynchrones résilientes grâce à la cohérence éventuelle. À travers des exemples concrets, elle explique comment intégrer le temps, gérer les échecs et aligner comportement technique, expérience utilisateur et attentes métier pour des systèmes plus robustes et évolutifs.
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Suzy ZimmerPictet Technologies
Pierre CharrassePictet Technologies
Many systems rely on synchronous interactions where users wait for operations to complete, creating tight coupling, fragile flows, and poor resilience when something goes wrong.
This talk explores how eventual consistency can be used as a deliberate solution to these problems by embracing time instead of hiding it.
Starting from a simple synchronous workflow, we examine how blocking interactions, retries, and failures create cascading issues across system boundaries. We will then rethink this flow using an event-driven approach, showing how eventual consistency allows systems to become more resilient, scalable, and aligned with real-world constraints.
Through concrete examples inspired by real production systems, we will highlight common pitfalls when moving from synchronous to asynchronous designs.
Beyond architecture, this talk introduces a mindset shift: systems should not be designed as if everything happens instantly. Instead, time and resources must be treated as a first-class concern, connecting technical behaviour with user experience and business expectations.
Key takeaways:
This talk explores how eventual consistency can be used as a deliberate solution to these problems by embracing time instead of hiding it.
Starting from a simple synchronous workflow, we examine how blocking interactions, retries, and failures create cascading issues across system boundaries. We will then rethink this flow using an event-driven approach, showing how eventual consistency allows systems to become more resilient, scalable, and aligned with real-world constraints.
Through concrete examples inspired by real production systems, we will highlight common pitfalls when moving from synchronous to asynchronous designs.
Beyond architecture, this talk introduces a mindset shift: systems should not be designed as if everything happens instantly. Instead, time and resources must be treated as a first-class concern, connecting technical behaviour with user experience and business expectations.
Key takeaways:
- Understand when synchronous designs create unnecessary waiting and fragility
- Learn how eventual consistency can be used as a practical solution, not just a trade-off
- Identify how to model and reason about time in event-driven systems
- Better align system behaviour with user and business expectations
Suzy Zimmer
Backend engineer and Chapter Lead working with Java, Spring Boot, and event-driven systems.
I work on distributed architectures where everything is asynchronous, consistency is delayed, and failures are part of the system. I also support teams in dealing with these realities through shared practices and technical guidance.
I’m especially interested in eventual consistency and the gap between how it’s described and how it actually behaves in production. Through my work and talks, I aim to challenge how we think about time, consistency, and system boundaries. Because in the end, business expectations and system behaviour are part of the same reality.
Outside of work, I like building small game prototypes. In all likelihood, it is another way to explore how systems behave (and break).
I work on distributed architectures where everything is asynchronous, consistency is delayed, and failures are part of the system. I also support teams in dealing with these realities through shared practices and technical guidance.
I’m especially interested in eventual consistency and the gap between how it’s described and how it actually behaves in production. Through my work and talks, I aim to challenge how we think about time, consistency, and system boundaries. Because in the end, business expectations and system behaviour are part of the same reality.
Outside of work, I like building small game prototypes. In all likelihood, it is another way to explore how systems behave (and break).
Pierre Charrasse
Lead Software Engineer in the banking sector in Luxembourg, I lead a development team and contribute to frontend governance at scale. I design and evolve critical distributed systems using Java/Spring Boot, TypeScript, and Angular, with a strong focus on performance, resilience, and long-term maintainability.
I combine hands-on engineering with leadership: mentoring developers, improving practices, strengthening CI/CD, and aligning technical decisions with business value.
Passionate about software architecture and complex systems, I have a particular interest in pragmatic solutions and the integration of AI into real-world products, topics I enjoy sharing through concrete, production-focused talks.
I combine hands-on engineering with leadership: mentoring developers, improving practices, strengthening CI/CD, and aligning technical decisions with business value.
Passionate about software architecture and complex systems, I have a particular interest in pragmatic solutions and the integration of AI into real-world products, topics I enjoy sharing through concrete, production-focused talks.