Hello, 👋 I'm Teun

I'm an entrepreneurial (big-) data-scientist and software developer with a focus on solutions for a sustainable future.

Teun Kortekaas

My projects



Reduced clothing returns, increased conversion and lower CO2 emissions. That is what we strive to accomplish at SizeBuddy.

SizeBuddy is your personal tailor that knows exactly which size you should order.

Together with Maurits Graaf and Diederik van Zantwijk, I have created SizeBuddy as a tool to help both clients and retailers. Using Artificial Intelligence we predict the clothes that fit you best, simply based on what you are already wearing.

Calendar Clock

Calendar Clock

The Calendar Clock is a clock with a messaging functionality that supports those with reduced awareness of time and/or memory problems. It shows the part of the day and time (analogue or digital) and shows important agenda items, reminders and/or personal messages. These messages can be created/edited/deleted on the user's device.

Calendar Clock participated in several start-up contests and has over 10.000 daily active users!



Gebakplaats, founded early 2019, is an online marketplace for pastries (kind of like eBay for pasty) where hobby bakers and those who like pastry come together. Hobby bakers offer their services and those looking for pastry or that are searching a baker to bake something special, can find each other on Gebakplaats.

With help from our local coordinators, with the Foodbank-initiative, Gebakplaats connects 12 local Foodbanks to volunteering bakers. This way, kids from poorer families can apply for a free birthday cake! This initiative has been featured in several newspapers, in radio interviews, and on local and national television.

Even after so many years, Gebakplaats still attracts over 5000 unique users each month!



Palbum offers a fresh new way to share adventures with groups of friends. People can customise their own profile, make a group profile with friends and upload albums and photos. With two fellow students I further developed Palbum and we ended up reaching the finals of the TU/e contest together!

About me

I am a student who is passionate about entrepreneurship and driven to acquire new skills through product development. I find immense satisfaction in contributing to projects that hold societal value. Witnessing enthusiastic users actively engage in co-creating my products is a source of inspiration for me. I like that the diverse range of products broadens my skill set in non-computer related areas.

I'm especially interested in the data-intensive systems domain, which I am currently writing my thesis in. I am happy that I am able to combine my wide knowledge in different computer science domains and I am thrilled by the prospect of contributing meaningfully to this dynamic field.

Follow me on LinkedIn or check out my GitHub.


  • Completed Bachelor/Master Computer Science and Engineering at the Eindhoven University of Technology
  • Gym fanatic
  • Loves tennis
  • Learning Bulgarian
  • Learning Piano
  • Awarded as 25 under 25
  • Finalist at the TU/e contest
  • Finalist at the ECDT/Jain Global Challenge/CareTech contests


  • General: Java / Python
  • Back-end: Django / PHP / Node JS
  • Front-end: HTML / JavaScript / CSS / React JS
  • Cross-platform apps: Flutter
  • Provable programming: Dafny
  • Cloud-based platforms: Firebase
  • Databases: NoSQL / SQL / PostgreSQL
  • Data-intensive systems: Spark / MapReduce / Hadoop
  • E-commerce platforms and APIs: Shopify / Magento / WooCommerce
  • / BigCommerce / Wix / CCV Shop / Mijnwebwinkel / Square
  • Browser extensions: Manifest V3