System Engineer - Application Networking (f/m/d) - onsite or remote / home office

1&1 Mail & Media Applications SE | IT Cross Functionality / IT Security / IT System Administration | Karlsruhe / Berlin / Munich | Permanent | Full-time | Experienced professionals | Reference ID: 4336

  • Tasks that ignite your passion

    Are you interested in topics such as load balancing, Edge Gateways, DDoS Protection, and SDN in a highly available and load-intensive modern infrastructure for more than 43 million users? We handle massive operations: hundreds of petabytes of storage, 3.5 billion active logins per day, and nearly half an exabyte of internet traffic annually. We don’t just use technology; we push it to its limits, break it, then innovate on solutions that lead the industry forward. Our commitment to active-active and high-availability environments is proven and sustained.

    You enjoy working in the context of such cutting-edge technologies, such as Kubernetes, and understand the concepts and requirements of highly available large-scale infrastructures? You’d like to work on innovative application networking standards that create real value for our customers and users? Do you believe that collaboration is the key to successful solutions? Then we are looking for you! Work with your team and colleagues to develop new application delivery and load balancing solutions for Germany's leading email and cloud providers WEB.DE and GMX.

    • You will design, develop, and operate our future application network infrastructure with several distributed data centers in close cooperation with experts and colleagues and will be involved in architectural decisions.
    • You evaluate and assess new technologies and products in the areas of load balancing, edge gateways, firewalls, web application firewalls, DDoS protection and SDN.
    • You will work "hands-on" on sustainable solutions from concept via go-live to shutdown, including automating processes and creating transparency about the status of systems.
    • You are the contact person for technical questions, interface between data center and application operations and support colleagues in the use and optimization of load balancing.
    • You keep the systems running, identify anomalies and get to the bottom of them - also as part of a 24/7 on-call service.

Advantages you enjoy

Lived corporate culture

Transparency, open communication and short decision-making processes

Wide range of further training

E-learning, seminars, conferences and mentoring

Renowned TEC-Campus

Conferences, lecture series, courses, open source projects, community meetings, user groups

Active health care

Sports and fitness classes, lectures, discounts at fitness and health centers, fresh fruit and drinks for free


Generous subsidy for job bike leasing and the job ticket

Flexible working models

Home office, mobile office, flexible working hours, trust-based working time arrangements

Financial benefits

Company pension scheme, discounts on our products and various leisure activities

Legendary events

Summer and winter parties, additional workshops and team events

  • Your qualifications which inspire us

    You have several years of experience in the operation and development of high-performance (application) networks and load balancer architectures? You have a technical degree or a comparable qualification? You strive for Infrastructure-as-Code, and quality and sustainability are your focus? You are passionate about agile and DevOps principles and continuous learning in a collaborative environment? You are a true team player, and your work attitude is "hands-on"? Then we are looking forward to your application!

    • You are familiar with technologies such as L7 load balancers and the relevant protocols such as HTTP and TLS, ideally already in interaction with Kubernetes.
    • You already have experiences with L3 routing, BGP and VXLAN and are interested in systems for attack detection and defense on application (WAF) and network level (DDoS).
    • You have solid methodological skills in design and architecture of scalable infrastructures and are familiar with Git and CI/CD pipelines.
    • You are Linux literate and an advocate of smart use of automation frameworks.
    • You have strong communication skills in English and are enthusiastic about modern network architectures.
  • Good to know
    • Our corporate culture: „You“ culture and no dress code, flat hierarchies, open and transparent communication
    • Individual development opportunities: diverse training courses, e-learning and internal communities, language courses, mentoring
    • Events: Slack Days, open source projects, meet-ups
    • Relocation service: support with the relocation to Germany
    • Benefits and additional services: company pension scheme, capital-forming benefits, discounts on own products, job ticket, bike leasing, corporate benefits portal
    • Attractive working conditions: 30 days holiday, hybrid working 2 days home office/week or remote work, full-time and part-time arrangements, free choice between Linux, Mac or Windows
    • Social: team events, summer and winter parties, family and care service, sports and fitness programmes, subsidised canteen, free fruit and drinks, health courses
    • Topics that are also important to us: Sustainability, diversity and our values and leadership principles - find out more on our website

We are brand. With GMX, WEB.DE and and over 43 million active users, we are the leading email and communication platform in Germany, Austria and Switzerland.

We are future. Our services and apps simplify digital life from cloud storage to news and ID management.

You are at home. Your digital passion finds a professional home with us. Your strength makes us stronger, your expertise complements our ideas, your success becomes visible. Together we shape the digital future.

Diversity enriches. Different cultures, nationalities, genders, age groups, sexual orientations and religions as well as people with disabilities - we desire diversity and encourage it. Because only teams that reflect all facets of society offer the best framework conditions for creativity and make a company productive and distinctive. We value diversity and welcome all applications.

Apply now

We look forward to receiving your application, including your salary expectations and the reference number given above. Please use our online application form. If you have any questions about the position or the application process, please send us an email.

1&1 Mail & Media Applications SE
Recruiting & Candidate Management
Brauerstraße 48
D-76135 Karlsruhe

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