About

I'm Sebastiaan — a Mendix Product MVP and Expert Developer based in the Netherlands, currently working as Senior IT Engineer at Nederlandse Spoorwegen (Dutch Railways). As part of the Mendix Platform Team, I support product teams across the organisation — coaching developers at every level, developing generic components and services, and occasionally disappearing down a Mendix platform rabbit hole so product teams don't have to.

My work is driven by a few core beliefs: developer experience should never be an afterthought, privacy is non-negotiable, and self-hosting is worth the effort. I prefer understanding every layer of my stack over relying on abstractions I can't inspect.

Beyond work, I'm deeply interested in aerospace technology and the local space community. What started as participating in hackathons eventually led to a Global Nominee selection at NASA's Space Apps Challenge in 2017 and a FabSpace 2.0 Award for Best Use of Earth Observation Data in 2018. That momentum inspired me to found Space Society Twente and organize the 2018 and 2019 Dutch editions of the NASA Space Apps Challenge.

These days, when I'm not wiring up containers, debugging DNS, or playing around with AI agents, I write about what I learn on my blog. I believe in sharing knowledge openly — the best documentation is the kind someone actually needed.

A brief history

My journey into tech started early. I've been building and breaking software since the age of 16 — back when parental controls weren't a thing — when I published MetroTour, a Tour de France application that reached over 10.000 users, which eventually snowballed into freelance work for the municipality of Enschede, local start-ups, and the ITC Faculty of Geo-Information Science and Earth Observation.

Before I started solving complex problems for a living, I obtained a Master's degree (Cum Laude) in Business Information Technology from the University of Twente, specializing in Enterprise Architecture and IT Innovation & Management, alongside an Honours Degree in Change Management & Leadership. My research focused on incorporating privacy trade-offs into the design of Mobility-as-a-Service solutions and estimating the environmental impact of human-computer interaction methods.

After graduating, I spent nearly five years at CGI Nederland in the public transport sector, where I ended up as Principal IT Architect — guiding a DevOps team, developing standards for Mendix teams, and presenting at community meetups.

Since 2024, I'm a certified Mendix Expert Developer and Product MVP, recognized for my contributions to the Mendix developer community — from test automation tooling to presenting at meetups and coaching teams across the ecosystem.

Experience

  1. Senior IT Engineer

    Nederlandse Spoorwegen

    Part of the Mendix Platform Team, supporting product teams across the organisation. Development and operations of Mendix applications in the public transportation domain. Coaching developers at every level and developing generic components and services to improve team velocity and product delivery.

  2. Principal IT Architect

    CGI Nederland

    Led a Scrum/DevOps team of 5 Mendix developers. Coached junior to senior developers on core software development concepts including DevOps, TDD, SOA, and performance best practices. Responsible for R&D of DevOps and Test Automation tools (including Playwright) for client projects. Presented at Dutch Mendix Community meetups and coordinated university outreach and recruitment.

  3. Quality Assurance Engineer

    CGI Nederland

    Increased test coverage of 3 Mendix applications with FitNesse. Developed new testing standards and Best Practices for Mendix teams. Collaborated with the centralized DevOps platform team to support Mendix test tooling in CI/CD environments. Monitored implementation of Mendix Development Best Practices.

  4. Information Architect & DevOps Engineer

    CGI Nederland

    Designed and supervised inter-organizational data distribution in public transport. Introduced Azure API Management in release processes for Mendix applications. Coached a Mendix development team transitioning from Agile/Scrum to a DevOps way of working. Designed and implemented CI/CD pipelines and consulted with SREs on expanding the DevOps toolkit for Mendix teams.

  5. Information Analyst & Software Engineer

    CGI Nederland

    Graduate intern turned full-time engineer. Developed a method to incorporate privacy trade-offs in Mobility-as-a-Service design. Researched mobility data platforms and designed data-driven service architectures for public transport. Consulted on long-term information management strategies and advised on intellectual property development for Transport & Logistics.

  6. MSc Business Information Technology (Cum Laude)

    University of Twente

    Specializations in Enterprise Architecture and IT Innovation & Management, with electives in Data Science. Graduate research on privacy in Mobility-as-a-Service at CGI. Teaching Assistant for BIT courses, delivering workshops and lectures on UX/UI to ~100 students. Developed a real-time geospatial analysis tool for ITC's research on quality of life in Enschede.

  7. Honours Degree

    University of Twente

    Change Management & Leadership.

  8. President & Founder

    Space Society Twente

    Founded Twente's first space-focused student association, creating a platform for students and space industry representatives to collaborate on research, CubeSat development, and a rocket program. Grew the network to 100 people and 17 partner organizations in two years. As NASA Local Lead for the Netherlands, organized the 2018 and 2019 Dutch editions of the International Space Apps Challenge.

  9. BSc Business & IT

    University of Twente

    Minors in Geo-Information Systems and Philosophy of Science & Technology.

  10. Freelance Software Developer

    Enapptic

    Notable projects include MetroTour (Tour de France app, 10.000+ users), a registration and badge system for Business Days Twente (2.500+ users), and smart home integrations for Athom's Homey platform. Also designed and developed (Geographic) Information Systems and provided pro-bono Business IT consulting for non-profits in the Twente region.

  11. Freelance Editor

    myWindows.nl / WP7.nl

    Editorial team member at the Netherlands' leading Windows Phone news website. Wrote app reviews, analysed tablet adoption in Dutch education, and authored explainer series on emerging technologies such as NFC.

Certifications

2023

Mendix Advanced Developer

Mendix

2023

Mendix Intermediate Developer

Mendix

2021

Mendix Rapid Developer

Mendix

Honours & Awards

  1. Mendix Product MVP

    Mendix

    Recognized for contributions to the Mendix developer community, from test automation tooling to presenting at meetups and coaching teams.

  2. Best Part-Time Board Award

    Student Union — University of Twente

    Recognized for growing Space Society Twente into a mature community and organizing events including NASA's International Space Apps Challenge.

  3. Winner — Supply Chain Hackathon

    University of Twente & TKI Dinalog

    Visualized transport logistics data from CGI and DPD using 3D graphics (KeplerGL) to aid data-driven decision making.

  4. Best Part-Time Board Award

    Student Union — University of Twente

    Recognized for founding Space Society Twente and establishing a platform for students and space industry representatives to collaborate.

  5. FabSpace 2.0 Award (Best Use of Earth Observation Data)

    FabSpace 2.0 — ActInSpace 2018

    Awarded for Vindo, a mobile app using Copernicus data to help people find cities matching their environmental needs.

  6. Global Nominee — Space Apps Challenge

    NASA

    Selected as global nominee with UberWasser, a beach safety app integrating satellite data and in-situ measurements.

Publications

  1. Inner Join Privacy: Incorporating Functionality-Privacy Trade-Offs in Mobility-as-a-Service Solution Design Methods

    MSc thesis

  2. Talking to Bots: Estimating the Environmental Impact of Human-Computer Interaction Methods

    BSc thesis