WAF Internship

Cyberfusion; Eindhoven; On-site; EUR 12,000 - 17,000; Full time

Job summary

Cyberfusion is hiring an intern to design and build the next generation of Core's bot and web application firewall layer at the TU/e campus in Eindhoven. You will work closely with two DevOps engineers to tackle end-to-end security and infrastructure challenges while engaging directly with technical customers.

We value Linux and open source dedication, deep problem-solving, and a strong drive to learn. Fluency in English is required, Dutch is a plus, and a JWT is not necessary for this role.

Qualifications

• Internship position for WAF-focused engineering at TU/e campus, Eindhoven.
• Dutch residents or work-permit holders; VOG required.
• Strong foundation in Linux, open-source tech, and modern infrastructure.

Responsibilities

• Design and build Core's new bot and web application firewall layer end to end.
• Collaborate with two DevOps engineers and interact with technically oriented customers.
• Contribute across DevOps domains; plan, prioritize, and take initiative.

Skills

Linux affinity

Open source

Problem solving

English communication

Team collaboration

Tools

Python

PHP

FastAPI

Laravel

MariaDB

Redis

RabbitMQ

Elasticsearch

Jaeger

Prometheus

Debian

Proxmox

Ansible

Borg

Dovecot

PowerDNS

Samba

Ubiquiti

VyOS

Oxidized

LibreNMS

Uptime Kuma

Sensu

NetBox

FleetDM

GitLab

passbolt

listmonk

Job description

Internship

Location: TU/e campus, Eindhoven WAF Internship

Design and build Core's new bot and web application firewall layer - end to end, alongside two DevOps engineers.

We only hire Dutch residents or persons holding a work permit. A Certificate of Conduct (VOG) is required.

WAF

Cyberfusion

Meet Cyberfusion.

We build Core: the most forward-thinking managed hosting platform in the Netherlands - where hosting, monitoring, security, and optimisation are woven together at a deep level.

Our customers are agencies, SaaS companies, webshops, and large platforms that don't have in-depth hosting knowledge in-house. For that they have us: a rock-solid foundation for all their projects, full of features for web professionals.

Our infrastructure runs webshops taking orders, portals where people log in, applications processing invoices. Every minute of the day. Do we do our job well? Then nobody notices. And that is exactly the point.

The project

A steady share of every website's traffic is automated. Some of it is welcome: search-engine crawlers, link previews from Slack and WhatsApp, and uptime monitors. But a large share is not: vulnerability scanners, scrapers, credential-stuffing tools, AI training crawlers, small DoS attempts.

We already tarpit, rate-limit, and block on the basis of smart patterns. That's no longer enough. Time for a more intelligent layer.

Your work

With plenty of freedom and independence, you get to work on integrating a more intelligent WAF into Core. Every side of DevOps comes past: you'll need to enjoy that variety and challenge. Since we're a small team, you'll also be in direct contact with -technical- customers yourself: web professionals who build websites and applications.

You're well supported by two DevOps engineers. We do expect you to take initiative, plan well, and set your own priorities.

Mentality

01 / 08 Linux and open source to the bone. If someone says "Windows", what do you do? Exactly: run. Linux servers and open-source projects, on the other hand: you get just as fired up about them as we do.

02 / 08 You need depth and challenge. Making the most advanced managed hosting platform in the Netherlands tick takes serious engineering, and we do almost everything ourselves. You work with every layer of infrastructure. The work is varied, deep, and never the same.

03 / 08 You don't need to know everything on day one, but... We don't expect you to know every tool in our stack inside and out. We do expect you to have a foundation - we're not going to walk you through the shell - and an enormous drive to learn everything.

04 / 08 Quality first, deadlines respected. You build things you're proud of - you have the freedom and time for that. At the same time, you understand that some things simply have to be done on time.

05 / 08 Getting things done. When things don't work right away - and in our field they rarely do - you come up with creative solutions. "I don't get it" isn't in your vocabulary.

06 / 08 You make decisions and document why. After interesting discussions, you pick a direction, you can put your choices into words, and you document them well.

07 / 08 Proactive communication. If you can't keep an agreement, you let everyone involved know in time. We're very strict about this, because the importance of what we do demands it.

08 / 08 Available when it truly matters. In the (unlikely) event that a major incident requires all hands on deck, you're there. No Elon Musk walks around here, but this is the reality of mission-critical infrastructure.

Profile

• We don't expect you to know it all yet - just plenty of affinity. Terms like 'gateway', 'bash' and 'KVM' don't scare you.
• You can understand a complex landscape of interconnected systems. This is about your level of thinking, not about knowing every tool.
• You want to master your craft. You may even need challenges to stay sharp and engaged. Aside from the work itself being challenging - and staying that way - we support you with a solid training and choice budget.
• You write and speak fluent English, and preferably Dutch too.

Stack

Self-hosted. Open source.

Our stack has been running on our own infrastructure and open-source software from day one. Out of conviction, morality, and sovereignty, back when that last word wasn't hip yet.

Languages

• Python
• PHP

Frameworks

• FastAPI
• Laravel

Software

• MariaDB
• Redis
• RabbitMQ
• Elasticsearch
• Jaeger
• Prometheus

Infrastructure

• Debian
• Proxmox
• Ansible
• Borg
• Dovecot
• PowerDNS
• Samba

Networking

• Ubiquiti
• VyOS
• Oxidized
• LibreNMS

Monitoring & operations

• Uptime Kuma
• Sensu
• NetBox
• FleetDM

Internal tooling

• GitLab
• passbolt
• listmonk

Curious what we offer customers? View the Core tools →

Neurodivergent or need adjustments? Have a neurodivergent profile (ADHD, autism, dyslexia, or anything else) or need adjustments for another reason? Let us know. We can send questions in advance, give you extra time, arrange a quieter moment or space, reduce stimuli, or use a different conversation format. Whatever helps you show what you can do. Read more about neurodiversity

Prefer speaking to a human? Call [phone] or email [e-mail]. Full contact details: https://cyberfusion.io/talk.