Jan-Hendrik Kuperus

Jan-Hendrik Kuperus

Director / Architect @ Yoink

Utrecht, The Netherlands

Jan-Hendrik is a passionate developer who is not afraid to break something open in order to find out how it works. He then likes to share the knowledge he picks up, because he believes teaching enhances both student and teacher. Apart from work, he tinkers with Arduinos and Raspberries at home, plays with LEGOs with his kids, runs the occasional Factorio speedrun and tries to find new ways to make the future greener.

Area of Expertise

  • Information & Communications Technology


  • Java
  • Java & JVM
  • Enterprise Java
  • CQRS & Event Sourcing
  • Scala Programming
  • Software Architecture

Evolution in Event Sourced Systems

Have you heard of Event Sourcing, but struggling to figure out how to apply it to real-world agile projects? Or maybe you are using Event Sourcing already, but wondering how you are going to live with that design-error you made at the start? Even if you have close to zero knowledge of Event Sourcing, this talk will have something for you.

Starting from a short introduction on what Event Sourcing is and how it changes the way you handle data and events in an application, this talk then continues to show you ways to facilitate change. From dealing with missing data in past events, to structural changes in aggregates and restructuring an event stream. The practical scenarios shown are inspired by close to 10 years of experience in building and maintaining Event Sourced applications with the Axon Framework.

The Case Against Frameworks

start.spring.io, ng init, AxonIQ Initializr... The ease of creating a new project is ever increasing. But at what cost? Frameworks give us a head start on any simple project, but they also bring baggage and opinions. This ignite talk is a highly opinionated call out to all developers to stay curious and stay practical.

Architecting a Sustainable Future

Sustainability is a lens through which the public has started scrutinising various industries. This lens is slowly increasing its focus on the field of IT. As software architects we are uniquely equipped to see this coming and be at the forefront of change.

During this talk, the audience is invited to test its knowledge on the energy usage of various common devices. This surprises most audiences and creates awareness about the need to collect data before we can effectively design new solutions.

Current efforts and organisations working towards greener IT are introduced and compared, as well as how anyone can join in these efforts.

At the end of this talk, the audience has been inspired to be critical about the way we design software systems and (cloud) infrastructures, invited to remain critical on decisions made in existing and new projects and they will leave with a hopeful sense of new possibilities.

Session duration is approximately 45-50 minutes.
Interaction with audience is done by a show-of-hands quiz.
Previously delivered at Rabobank Architecture Event.

J-Fall 2023

November 2023 Ede, The Netherlands

J-Fall 2022

November 2022 Ede, The Netherlands

Devoxx Belgium 2022

Hosted a BOF titled: Exploring Sustainability in Tech without the Guilt-Trips

October 2022 Antwerpen, Belgium

JavaZone 2022

Presented The Case Against Frameworks as a full length talk

September 2022 Oslo, Norway

J-Fall 2021

November 2021 Ede, The Netherlands

Jan-Hendrik Kuperus

Director / Architect @ Yoink

Utrecht, The Netherlands