Senior IT System Administrator (m/f/d)

Shape the future of wireless communication with us.

While our projects and teams have grown significantly, our internal IT still has considerable potential for expansion. This is exactly where you come in. We are looking for a highly experienced individual who not only operates our IT infrastructure, but also actively develops it, automates it and takes it to a new level.

Your tasks:

• Operation, maintenance and further development of our on-prem infrastructure (Proxmox cluster with several nodes and VMs incl. backup strategies)
• Administration and expansion of our network infrastructure (OPNsense Firewall, UniFi Fabric, VLANs, VPN - OpenVPN/WireGuard/Headscale)
• Operation and further development of our security stack (SIEM/EDR with Wazuh, Endpoint Security, Incident Detection)
• Responsibility for monitoring & logging (Loki, Grafana, Zabbix incl. alerting)
• Incident response incl. root cause analysis and sustainable troubleshooting (post-mortems)
• Automation of infrastructure and processes with Ansible (Linux, Windows, macOS) and scripting (Python, Bash)
• Integration and use of APIs (Google, Microsoft Graph, Atlassian, GitLab)
• Further development and review of IT security guidelines (e.g. password, security and AI policies)
• Support of our DATEV environment incl. SmartCard integration
• Administration of users, access and authorizations (AD, Google Workspace, Microsoft 365)
• Administration of our VoIP solution (3CX)
• Lifecycle management for hardware and end devices (Windows, macOS, Linux)
• 1st & 2nd level support for our employees (troubleshooting, onboarding/offboarding)
• Planning and implementation of IT projects (migrations, rollouts, infrastructure expansion)
• Development and maintenance of documentation in a mature environment

Your profile:

• Several years of experience in the independent administration of complex IT infrastructures
• Very good knowledge of Linux (e.g. Debian, Ubuntu, Arch) including in-depth troubleshooting (kernel, drivers, network)
• Experience with Windows Server and macOS environments
• Sound knowledge of network technologies (VLANs, STP/RSTP, LACP, routing, firewalls, VPN)
• Experience in operating virtualization environments (Proxmox/KVM, cluster operation, backups)
• Hands-on experience with automation (Ansible) and scripting (Python/Bash)
• Knowledge of SIEM/EDR and IT security (e.g. Wazuh, Elastic, Splunk)
• Experience with Atlassian Stack, GitLab and Directory Services
• Structured, solution-oriented way of working and a high sense of responsibility
• Willingness to familiarize yourself deeply with existing systems and to improve things sustainably
• Very good knowledge of German and English

What we offer:

Holistic development
From hardware-related firmware to the complete system: thanks to the close integration of hardware, software and in-house production, you can test and optimize your solutions directly in the real system.

Diversity & further development
Varied projects in different industries allow you to continuously learn and develop your skills - both technologically and methodically.

Creative freedom & responsibility
You take responsibility for your own modules or systems and actively help shape technical solutions and future fields of technology.

Stability & prospects
Permanent employment with long-term prospects, a lot of personal responsibility and very good development opportunities.

Team & culture
International, experienced team with flat hierarchies, short decision-making processes and a genuine interest in your ideas. We value pragmatic cooperation and technical quality.

Working conditions

• Flexible working hours (flexitime with core working hours 10:00-15:00)
• 1 fixed home office day per week + additional mobile work by arrangement
• Modern, bright offices in a central location in Dresden

Benefits & additional services

• Choice of Germany ticket (€55.10 subsidy) or JobRad (€54.90 subsidy) after the probationary period
• Free gym in the building