About

I'm Jasper Van Zeir, a Full Stack Development student at HOGENT and an active-duty Sergeant in the Belgian Armed Forces IT division since August 2025. In 2026 I'm transitioning to HOWEST for a dedicated Cybersecurity bachelor, with a long-term goal of joining Belgian Defence Cyber Command as a red team operator.

I deliberately started with full stack development - understanding how systems are built is what makes understanding how they break meaningful. I apply that in practice through CTF competitions (50+ challenges, 20+ writeups) and hands-on security research - currently focusing on web exploitation, network security, and offensive tooling.

Outside of that you'll find me training for triathlons, watching F1, or running sqlmap --level=5 against something I'm supposed to.

SGT · Belgian Defence50+ CTF Challenges20+ Writeups
Experience
2026 - 2029
Bachelor Cybersecurity
HOWEST - Upcoming

Dedicated cybersecurity degree focused on offensive security, ethical hacking, digital forensics, and secure software development. The next step after building a solid full stack foundation.

PentestingRed TeamForensicsOffensive Security
Aug 2025 - Present
Sergeant, IT Division
Belgian Armed Forces

Active-duty Sergeant within IT at Belgian Defence. Responsible for infrastructure support, system administration, and internal tooling. Gaining hands-on experience in discipline, responsibility, and professional operations.

InfrastructureSysadminNetworking
2024 - Present
Self-Study & CTF Competitions
HackTheBox · TryHackMe · BugForge

Actively building cybersecurity knowledge through 50+ CTF challenges and hands-on security labs. Documenting everything in 20+ writeups on GitBook. Focused on web exploitation, network security, and offensive tooling.

Web SecurityCTFHackTheBoxTryHackMePython
2023 - 2026
Bachelor Applied Computer Science
HOGENT - Full Stack Development

Full Stack Development track covering Java, C#, JavaScript, TypeScript, React, and MySQL. Deliberately chosen to understand how modern applications are built before specialising in how they break.

JavaC#ReactTypeScriptMySQLDocker
Certifications
TryHackMe
Pre-Security
2024
Verified
Hack The Box
Certified Penetration Testing Specialist (CPTS)
In Progress
Cisco
Cybersecurity Essentials
In Progress
Projects
01
Phishing URL Detector

AI-powered phishing URL detection tool using a Random Forest classifier trained on 11,000+ labeled URLs. Detects phishing patterns via URL structure, suspicious keywords, subdomain count, and special characters.

PythonMachine LearningScikit-learnPhishing Detection
02
Cybersecurity Portfolio

This site. Next.js 15, Tailwind CSS, gradient cursor library, dark design system. Active development.

Next.js 15Tailwind CSSTypeScript
Writeups & Blog
Docs
z3r0d4yj · Writeups & Docs
docs.jaspervanzeir.com · CTF writeups, exploit breakdowns, security research
Medium
z3r0d4yj · Blog
medium.com · Articles, security write-ups and thoughts
Download CV