Maarten Jacobs
CTO at Defacto - developing people since 1987
Groningen, Groningen, Netherlands
Summary
🤩
Rockstar🎓
Top SchoolMaarten Jacobs is a CTO and seasoned software engineer with 12 years of experience building pragmatic, user-focused systems from research prototypes to production services. Based in Groningen, he combines an MSc in Artificial Intelligence with a strong background in security and cryptography from PhD research, bringing rigorous thinking to product and architecture decisions. He has hands-on experience across backend development—contributing budget and audit features to the open-source Hours time-tracking app—and leads technology strategy at LearningSpaces while continuing software development at Defacto. Known for improving data consistency, localization, and export features, he bridges academic depth and practical engineering to deliver auditable, maintainable solutions.
12 years of coding experience
MSc, Artificial Intelligence, MSc, Artificial Intelligence at Rijksuniversiteit Groningen
Dutch, English
Github Skills (18)
ruby-rails10
rails10
ruby10
activerecord10
schema-design9
db-schema9
database-schema9
schema9
time-tracking9
database-design9
i18next8
csv8
i18n-js8
auditing8
csvhelper8
Programming languages (10)
Github contributions (5)
DefactoSoftware/Hours
Dec 2014 - Jan 2020
Time registration that doesn't suck
Role in this project:
Back-end Developer
Back-end DeveloperContributions:53 commits, 51 PRs, 69 pushes in 5 years 2 months
Contributions summary:Maarten focused on adding budget-related features to the time tracking application. This included adding a budget attribute to the project model, calculating the budget status based on entries, and allowing users to set a budget during project creation. Additionally, the user made changes to the audit logging functionality for projects, adding a route and view, and improving database schema consistency. The user also worked on localizing certain elements and improving the CSV export functionality.
railsregistrationtime-registrationruby
tarzan/leaked_passwords
Mar 2018 - Sep 2022
Checking for leaked passwords through haveibeenpwned v2 API using the hash-range checker
Contributions:22 commits, 7 PRs, 20 pushes in 4 years 7 months
leaksapipasswordshashchecker
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