Stefan Kroes
CTO at Booking Experts B.V.
Enschede, Overijssel, Netherlands
Summary
🤩
Rockstar🎓
Top SchoolStefan Kroes is a seasoned CTO and hands-on software engineer with over 16 years of professional experience and 20+ years working on web-based projects, primarily using Ruby on Rails. He blends deep backend expertise—illustrated by contributions to the ancestry ActiveRecord gem (adding cycle detection, depth caching and STI support)—with practical architecture and product leadership across telecom, finance and travel sectors. At Booking Experts he progressed from senior engineer to CTO, consistently taking on whatever the project needed from coding to interaction design and requirements analysis. Stefan has a strong track record modernizing OSS stacks and integrating systems at scale, having led migrations involving Ericsson, Tyk.io and Elastic in large telco environments. Based in Enschede and holding an MSc in Software Engineering from the University of Twente, he brings a pragmatic, performance-minded approach and a tendency to solve tricky data-integrity and traversal problems behind the scenes.
16 years of coding experience
23 years of employment as a software developer
MSc. Computer Science Software Engineering, MSc. Computer Science Software Engineering at University of TwenteVWO Science & Engineering and Science & Health, VWO Science & Engineering and Science & Health at De GSG Leo Vroman
Dutch, English
Github Skills (6)
ruby10
activerecord10
validation10
validations10
testing10
performance-optimization9
Programming languages (4)
Github contributions (5)
stefankroes/ancestry
Oct 2009 - May 2015
Organise ActiveRecord model into a tree structure
Role in this project:
Back-end Developer
Back-end DeveloperContributions:56 commits, 2 PRs, 2 pushes in 5 years 7 months
Contributions summary:Stefan contributed to the development of an ActiveRecord model that organizes data into a tree structure. They implemented cycle detection and validation, ensuring data integrity within the tree hierarchy. The user also introduced depth caching and related scopes, improving performance and providing new methods for tree traversal. Furthermore, the user addressed bugs and inconsistencies while adding support for STI (Single Table Inheritance).
railsrubyorganiseactiverecord-modeltree-structure
stefankroes/scribble
Nov 2014 - Dec 2014
Contributions:11 commits, 4 comments in 1 month
templatesimilarliquidrubytemplate-language
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.