---
title: 'System Administrator (Defence & Security) at Reaktor'
canonical: 'https://feeny.ai/job/system-administrator-defence-security-reaktor-helsinki-8pr9a389qkrn'
type: 'job'
last_seen: '2026-11-07'
---

# System Administrator (Defence & Security) at Reaktor

- **Company:** Reaktor
- **Location:** Helsinki, Finland
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2026-10-01
- **Last confirmed live:** 2026-11-07
- **Apply:** https://jobs.ashbyhq.com/Reaktor/254da29f-5309-487f-b5ab-990a62d6c720

## Job description

Reaktor’s Defence & Security Unit is looking for a System Administrator to join our internal IT team in Helsinki. Join Reaktor’s DefSec team, where agility, teamwork, and trust drive everything we do. We work on some of the most complex and mission-critical challenges in the industry, helping clients navigate an evolving landscape with cutting-edge solutions. Are you in your element when maintaining and building secure, automated IT environments that support world-class development work? Do you enjoy solving complex technical challenges hands-on while working alongside dedicated professionals? If so, you might be just the person we’re looking for.

## What you’ll be doing

- Systems Installation & Maintenance – Build and maintain DefSec’s internal IT systems that enable high-performing development work.
- Automation & Infrastructure Development – Maintain and improve automation for system maintenance, using state-of-the-art tooling.
- Security & Stability – Ensuring our environments are safe, compliant, and reliable.
- Cross-functional Collaboration – Partner with DefSec consultants, developers, and stakeholders to solve complex and multi-dimensional challenges.
- Support & Troubleshooting – resolving issues from hardware to networks and automation.
- Documentation & Knowledge Sharing – Document practices and systems, and actively share your learnings with the team.
- Continuous Improvement – Help evolve our internal systems and support organization, taking ownership of both day-to-day operations and longer-term infrastructure planning.

To thrive in this position, you’ll need:

- Minimum of 5 years of relevant experience in system administration or IT infrastructure roles.
- Strong knowledge of Linux (Fedora, CentOS, or similar).
- Understanding of IP networking, VPNs, and firewalls.
- Familiarity with certificate management and authentication mechanisms.
- Hands-on experience with scripting (Bash, Python, PowerShell, etc.).
- A proactive mindset with a focus on helping others and solving problems.
- Excellent communication skills to interact with both technical and non-technical stakeholders.
- Fluency in both Finnish and English (written & spoken)
- Willingness to work 100% on-site.

This position requires Finnish citizenship due to client and security regulations. The selected candidate must successfully complete a security clearance process.

Nice-to-have skills:

- Experience with Ansible or similar automation tools.
- Familiarity with Windows and macOS desktop administration.
- Coding experience in TypeScript, Python, or Go.

Why join us? For two decades, we’ve been developing qualities and capabilities for adapting, reacting, and supporting change – building Reaktor to hold up in a fast-paced environment while ensuring the well-being of our people.

While working at Reaktor, we’ll provide you with:

- An opportunity to work with our DefSec’s internal IT team to ensure our consultants have access to secure and efficient environments. Your work directly supports our critical security-focused software projects.
- The ability to impact how you work. Together with your team, you choose the approach, technologies, and methodologies you think will work best in any given situation.
- A community with as much support as your heart desires.
- A team that’s not only experienced but considerate as well – they all want you to succeed.
- Career development, helping you develop your skills further through guidance and/or courses, and giving you the opportunity to explore your career interests.
- A sustainable work-life balance and support for your daily life outside of work. (e.g., free moving day, Reaktor car share, sick child care services, office space to use for your private events, etc.).
- Many different hobby clubs, from winter swimming and running to knitting and archery, that bring people together outside of (and sometimes inside) office hours. Many of these are supported by Reaktor

Diversity, equity, and inclusion Together, we are committed to making Reaktor an environment that embraces and values all of our employees for the whole of who they are. We encourage applicants from all backgrounds to apply, knowing that studies show that members of underrepresented communities don’t apply for jobs unless they fully satisfy all of the requirements. If you're thinking twice about applying for this reason, we invite you to send us your application anyway. You could be just the person we're looking for. Read more about our DEI work[here](https://www.reaktor.com/dei).

## About Reaktor

## Company Overview
- **One-liner**: Reaktor is a global technology company that designs and builds category-defining digital solutions across industries, from software development and strategic design to AI and data capabilities.
- **Entity Type**: Private (pre-IPO; planning a listing on Nasdaq Helsinki)
- **Headquarters**: Helsinki, Finland
- **Founded**: 2000
- **Founders**: Not publicly listed

## Core Business
- Primary industries: aerospace & defense, finance, healthcare, industrial, gaming, retail, public sector
- Target customers: large enterprises, government agencies, and high-stakes organizations (B2B, predominantly enterprise)
- Mission / purpose: Create category-defining products that perform when it matters most, driven by a “Culture of Better” – iterative improvement, autonomy, and deep domain expertise

## Products & Services
- **Custom Solutions**: Embedded engineering, design, and strategy teams that partner with clients on mission-critical technology challenges. 97% net revenue retention (2025) and DORA scores 7.5–16% above industry average.
- **Productized Solutions**: Ready-made software products built from 25 years of domain knowledge, already deployed in defense and security markets.
- **Reaktor Ecosystem**: A network of >45 independently operating technology companies that Reaktor invests in or co-founds, providing engineering credibility, domain expertise, and a two‑decade network.

## Market Standing
- **Valuation / Market Cap**: Not disclosed (private pre-IPO)
- **Key Metric**: Estimated annual revenue of ~€190 million (based on company‑stated figures; exact numbers not confirmed in public filings)
- **Notable Investors/Partners**: No external venture investors; partners include ABB, ZAP Surgical Systems, and others across industries.
- **Growth Signals**: Planning an IPO on Nasdaq Helsinki; headcount of 700+ professionals across 9 offices on 3 continents; 58 nationalities; expanding productized software and AI/Data offerings; strong retention and quality metrics.

## Competitive Advantages
- Deep industry specialization (aero, defense, finance, healthcare, etc.) rather than generalist consulting
- 25 years of Nordic‑rooted agile practices and a culture of autonomy and continuous learning
- Full lifecycle partnerships – from problem identification to design, development, and long‑term maintenance
- Productized approach that turns accumulated domain expertise into scalable, reusable software
- Ecosystem model that extends reach and innovation capacity beyond a single firm

## Strategic Focus
- Initial Public Offering on Nasdaq Helsinki to accelerate growth and increase market visibility
- Growth of productized software business, especially in defense & security and other high‑stakes verticals
- Deepening AI and data capabilities (e.g., LLM applications, AI developers) integrated into every client engagement
- Continued expansion of the Reaktor Ecosystem through co‑founding and investing in independent technology companies

## Why Work Here
- **Culture**: “Culture of Better” – people‑first, Nordic values of trust, autonomy, and continuous improvement. 58 nationalities in a global, collaborative environment.
- **Work Model**: Hybrid; team‑specific agreements on on‑site vs. remote work depending on client and project needs.
- **Perks**: Minimum 25 vacation days, top‑class health benefits (including mental health support and ergonomic solutions), professional growth programs (mentoring, internal academies, external courses/books budget), 200+ hobby clubs, relocation support, latest tech equipment.
- **Growth**: Six‑month onboarding, strong emphasis on learning and mastery; opportunities to work on challenging, high‑impact projects across industries.
- **Autonomy**: Cross‑functional teams have freedom to choose tools, methodologies, and tech stacks.

## Sources
1. [reaktor.com – About](https://www.reaktor.com/about-us)
2. [reaktor.com – Careers](https://www.reaktor.com/careers)
3. [reaktor.com – Culture](https://www.reaktor.com/culture)
4. [reaktor.com – All Open Positions](https://www.reaktor.com/careers/all-open-positions)

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