Site Reliability Engineer (f/m/d) - Defense Products

at subsidary IONOS SE in Work from home
Full-time | Permanent | Professionals
Reference ID: I-249


About us

IONOS is the leading European digitalization partner for small and medium-sized businesses (SMB). The company serves around six million customers and operates across 18 markets in Europe and North America, with its services being accessible worldwide. With its Web Presence & Productivity portfolio, IONOS acts as a 'one-stop shop' for all digitalization needs: from domains and web hosting to classic website builders and do-it-yourself solutions, from e-commerce to online marketing tools. In addition, the company offers Cloud Solutions to enterprises who are looking to move to the cloud as their businesses evolve.   


Our team of highly motivated experts against cyber security attacks are looking for more teammates. As a Site Reliability Engineer you will develop and operate together with system administrators and network engineers our defense platforms which protect our hosting products and infrastructure. Besides the classical DDoS Mitigation, we are also responsible for modern web application firewalls, zero trust strategies or a content delivery network (cdn). In a culture which places great value on creative ideas, agile working methods, initiative, and participation you can expect the following tasks.

  • Development and adjustment of our defense logic to mitigate DDoS attacks on the network and application layer.
  • Optimizing current pipelines for automatic threat detection and mitigation and the reporting of those.
  • Support our system administrators to automate operational tasks and rollouts.
  • Provide interfaces for integration in our hosting products for other teams.
  • Administration and troubleshooting of our high-available and complex infrastructure including participation in an on-call service rotation.
  • Support company goals through efficient operating architecture, active lifecycle management and lean processes in an agile DevOps environment.


You have studied computer science or have completed comparable education. You have a keen interest in security topics, good network knowledge, and have the following qualifications.

  • Several years of experience in system near development of highly available software artifacts, written in programming or scripting languages: Go, C, Python, PHP, Bash.
  • Experience in writing application logic with Lua as a scripting language in combination with nginx would be ideal.
  • Practical experience of operating nginx as reverse proxy or web application firewall.
  • Infrastructure as code and automation are important parts of your own way of working.
  • Additional experience about BGP, flowspec, anycast routing as well as the basic understanding of network protocols on linux systems are not foreign to you.
  • Good analytical skills to evaluate DDoS attacks, implement countermeasures, and continuously develop our defense platforms.
  • Like us, you are a fan of Open Source, especially Linux.
  • The ability to communicate with an international team fluently in English, German is a benefit.


  • Hybrid working model with home office option.
  • Flexible working hours through trust-based working hours.
  • At some locations a subsidized canteen and various free drinks.
  • Modern office space with very good transport connections.
  • Various employee discounts for activities and products.
  • Employee events such as summer and winter parties, as well as workshops.
  • Numerous training and development opportunities.
  • Various health offers, such as sports and health courses.

apply online now

We value diversity and welcome all applications - regardless of, for example, gender, nationality, ethnic or social origin, religion, disability, age as well as sexual orientation and identity, physical characteristics, marital status or any other irrelevant factor subject to applicable law.


Recruiting Team IONOS

Hinterm Hauptbahnhof 3-5
D-76137 Karlsruhe