This position is open only to Ukrainian citizens within Ukraine (preferably Kyiv or Lviv).

Our Infrastructure & Hardware department is looking for an infrastructure geek as we continue our purposeful, long-term growth, built on a stable and dedicated team. We welcome candidates at all experience levels — from junior to senior.

We take on mission‑critical projects and prioritise building for decades, rather than just until the next release. We put strong emphasis on developing our new team members, offering an extended onboarding period, a clear PDP, and direct involvement from the Department Head from day one. Tell us where you can add value, and we will provide the tools, knowledge, and support for you to succeed.

What makes you a great match #

• Curiosity: In addition to knowing how things work, you also want to know why they work that way.
• Solid communication skills are a must — because mind-reading isn’t part of the job.
• A natural inclination to keep everything around you organised, design conventions and follow them.
• Strong logical thinking (by the third page of the detective story, you already know who the killer is).
• You’d rather automate it all, instead of doing it each time by hand.
• You have the persistence to complete the “boring” parts of the job, like writing technical documentation or running tests.

What you’ll do #

• Maintain the infrastructure of commercial projects with huge social impact, as well as internal — for development and R&D purposes.
• Design and implement HA systems.
• Learn what “proper security” means and participate in security assessments.
• Experiment with unconventional tasks.
• Enhance SDLC for our products.
• Participate in formulating internal procedures, standards, and workflows.
• Collaborate with a team of talented engineers when doing everything above.

Requirements #

• Good knowledge of Linux systems and networking.
• Understanding of the main Internet systems and services.
• Good skills in programming in at least two scripting languages: Bash && (Python || Ruby).
• Familiarity with Docker and KVM.
• Basic familiarity with IaC tools (at least one of Ansible/Chef/Puppet/Salt) and IaC approaches.
• Troubleshooting skills.
• Familiarity with monitoring tools and basic principles.
• Sufficient knowledge of English to read this entire job posting and understand everything.

Nice to have #

• Knowledge of main cryptography and security protocols, algorithms, approaches and instruments.
• Experience of PostgreSQL/MySQL and other database systems.
• Understanding of and hands-on experience with computer hardware and networking equipment (servers, embedded systems, routers, switches).
• Experience in at least one of the non-scripting languages: C/C++/Go/Rust.
• Understanding of key software development principles and lifecycle.

Hiring process #

1. Resume review — 5-7 business days.
2. Pre-intro questionnaire review - 3-4 business days.
3. Introduction call with the Head of Infrastructure & Hardware Engineering.
4. Test task — 2 hours working with a virtual machines.
5. Technical interview with several team members.
6. Background check.
7. Offer discussion.

What we offer #

• Opportunities to work across technologies and projects: cryptography, software engineering, information security, ML security controls, cryptographic protocols, hardware protection, reverse-resilient mobile apps, and web apps for millions of users.
• Quarterly performance reviews, regular one-on-one meetings with your manager, and ongoing support to help you succeed and grow professionally.
• Quarterly compensation reviews, aligning pay with performance and market benchmarks.
• Performance and reward bonuses.
• 21 business days of vacation, plus sick, mental health, and emergency days to use when genuinely needed.
• Combination of in-office and remote work as needed, flexible scheduling, and a winter slowdown period.
• Conferences, books, courses, internal knowledge sharing, workshops, writing blog posts and research papers, giving talks, and contributing to open-source parts of our products — choose what aligns with your professional goals.

Why work at Cossack Labs? #

You’ll work alongside PhDs in information security and cryptography, contributors to infosec community standards, specialists in rare security topics, and business-centric security engineers with broad experience. Some have worked in infosec since the 1990s, helping shape the industry and write the standards it relies on today.

For newcomers, we offer detailed onboarding during the first weeks. At Cossack Labs you’ll discover what works for you and what you need to learn next, developing through hands-on work on challenging problems, mentoring, and continuous learning with personal development plans to guide your growth.

Working at Cossack Labs, you’ll be at the cutting edge of technology and real-world security projects alongside highly skilled professionals who genuinely care about building a safer and more secure future.