Windows Engineer | Mid-Senior | C#/.NET

Nord Security; Warszawa; On-site; PLN 120,000 - 180,000; Full time

Benefits offered by this job

Training & mentorship

Extra vacation days & sick days

Private health insurance (PL)

Wellness & mindfulness benefits

In-house gyms & fitness support

Workation & travel opportunities

Work from anywhere vibe

Job summary

Nord Security’s B2B team builds cybersecurity products that help businesses protect their data. This role focuses on Windows application development using .NET, with a strong emphasis on Windows API, debugging, and agile collaboration.

You will own features end-to-end and contribute to architectural decisions while working with cross-functional teams in Warsaw. We value 3+ years of experience, deep API knowledge, and excellent English.

Qualifications

• 3+ years of experience in Windows application development using .NET.
• Deep familiarity with Windows API, including multithreading, IPC, and memory management.
• Excellent debugging and troubleshooting using Windows tools.
• Experience in Agile methodologies and Git workflows.
• Proficient English language skills.

Responsibilities

• Design, develop, and maintain Windows applications and system components (Services, IPC, networking, GUI, APIs, and drivers).
• Collaborate with designers, QA, and Product Owner to extend and improve the product from early discussions to final delivery.
• Own features end-to-end: research, write clean code, and ensure release.
• Contribute to architectural decisions and shape technical direction.

Skills

.NET

Windows API

Debugging

Agile

Git

English

Job description

At Nord Security’s B2B team, we build cybersecurity products that enable businesses to protect themselves and their data.

From product and engineering to sales, marketing, and data — our teams work closely together to deliver secure, scalable solutions trusted by companies around the world.

Your impact? Empowering businesses everywhere to keep their people, systems, and data safe.

Main Responsibilities

• Design, develop, and maintain Windows applications and system components - Services, IPC, networking, GUI, APIs, and drivers.
• Collaborate with designers, QA, and the Product Owner to extend and improve the functionality of our product, from early technical discussions to final delivery.
• Take ownership of features end-to-end: research solutions, write clean and maintainable code, and see your work through to release.
• Contribute to architectural decisions and help shape the technical direction.

Core Requirements

• Proven Experience: minimum 3+ years of experience in Windows application development using .NET.
• Windows API Proficiency: deep familiarity with Windows API, including experience with multithreading, inter-process communication, and memory management.
• Debugging & Troubleshooting: excellent debugging and troubleshooting skills with experience using Windows debugging tools.
• Experience in Agile & Git.
• Profound English language skills.

Bonus Points For

• Good understanding of networking protocols (TCP/IP, UDP), VPN technologies (OpenVPN, WireGuard, IPSec), and network security principles.
• Good understanding of security best practices and a commitment to writing secure code.

What We Offer

• Sharpen your edge: training, mentorship, and room to grow — always.
• Take the time you need: extra vacation days, sick days, and time off when life calls.
• Get premium healthcare: private health insurance in Lithuania and Poland — fully covered.
• Protect your peace: enjoy free subscriptions to Calm, Headspace, and Mindletic, and our own resilience and mindfulness trainings.
• Own your fitness: in-house gyms, sport cards, online workouts, and personal guidance — on us.
• Pack your bags for workation: experience our company-wide trip abroad to the fullest.
• Work from anywhere: work from wherever keeps you in the zone.
• Celebrate your milestones: birthdays, weddings, and new family members — all deserve a gift.
• Parent with ease: children’s summer camps and flexibility around the schedule — because parenting never pauses.
• Join the party: team building and company events people talk about for months.
• Unlock Cyber City: coffee bar, open gyms, kids’ room, music room, massage chairs — our Vilnius HQ is yours to enjoy.

Kindly refer to our Privacy Notice for Recruitment Candidates for comprehensive information regarding our data handling procedures throughout recruitment processes.

We expect all candidates to provide accurate and complete information during the recruitment process. While limited use of AI tools to refine application materials is acceptable, candidates remain fully responsible for ensuring that their submissions reflect their own qualifications, skills, and experience. Any failure to do so may negatively affect participation in the recruitment process. If broader AI assistance is allowed for a particular role or stage, we’ll let you know in advance.

By submitting your application, you acknowledge that it may be processed using automated tools for evaluation purposes. As part of our recruitment process, we may use an AI-based application review tool to help assess applications based on skills and experience relevant to the role. This technology is used to support - not replace - human decision-making, and every application is ultimately reviewed by a recruiter.

If you would like more information about how AI is used in this process or wish to exercise your rights under applicable data privacy laws, please contact us at [e-mail]. Should you prefer to opt out of the automated evaluation, please submit your application directly to [e-mail].