---
title: 'Lead System Administrator (Defence & Security) at Reaktor'
canonical: 'https://feeny.ai/job/lead-system-administrator-defence-security-reaktor-helsinki-62hkmv433n8s'
type: 'job'
last_seen: '2026-11-07'
---

# Lead System Administrator (Defence & Security) at Reaktor

- **Company:** Reaktor
- **Location:** Helsinki, Finland
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2026-10-05
- **Last confirmed live:** 2026-11-07
- **Apply:** https://jobs.ashbyhq.com/Reaktor/162e06ed-fe7f-4550-b0b5-c990b21ed335

## Job description

Reaktor’s [Defence & Security Unit](https://www.reaktor.com/industries/defense-and-security)is looking for an experienced, hands-on Lead System Administrator to join our internal IT team in Helsinki. Our team builds and maintains secure and reliable IT environments that DefSec’s development teams depend on. The work ranges from daily maintenance and troubleshooting to automation, security, and longer-term infrastructure development.

As a Lead System Administrator, you will work hands-on as part of the team: building and maintaining systems, developing automation, and solving technical problems. Alongside your technical responsibilities, you will take ownership of the overall flow of the team’s work. You will keep the backlog clear, bring together technical and business needs, and facilitate prioritisation together with the team and business stakeholders. In our low-hierarchy environment, your role is to help the team maintain a shared understanding of what matters most, navigate competing requirements, and move the right work forward.

## What you’ll be doing

- Owning, maintaining, and refining the team’s backlog to ensure clear direction and steady workflow.
- Setting priorities for upcoming work based on business impact, urgency, and technical dependencies.
- Building and maintaining DefSec’s internal IT systems.
- Developing automation for system maintenance and infrastructure management.
- Ensuring that our environments are secure, compliant, stable, and reliable.
- Troubleshooting issues across hardware, operating systems, networks, and automation.
- Working closely with developers, business stakeholders, and consultants to understand and translate their needs into actionable work.
- Improving documentation, sharing knowledge, and developing the team’s technical practices.
- Contributing to both day-to-day operations and longer-term infrastructure planning.

## What we’re looking for

- At least 8 years of relevant experience in system administration or IT infrastructure.
- Proven experience in gathering requirements, prioritising a team backlog, and balancing conflicting demands.
- Demonstrated ability to work directly with business stakeholders and align technical priorities with business needs.
- Good communication skills with both technical and non-technical stakeholders.
- Strong knowledge of Linux, such as Fedora, CentOS, or similar.
- Good understanding of IP networking, VPNs, and firewalls.
- Familiarity with certificate management and authentication mechanisms.
- Hands-on scripting experience with Bash, Python, PowerShell, or similar.
- Fluency in both Finnish and English (written & spoken).
- Willingness to work primarily on-site in Helsinki.
- 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.
- Programming 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.

Interested? Drop us a line – We'll be happy to hear from you!

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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