Linux Hacker & Nix Wizard (Senior / Expert)

Virtus Lab sp. z o.o. (Ltd.); Kraków, Kielce; On-site; PLN 180,000 - 280,000; Full time

Job summary

Virtus Lab sp. z o.o. (Ltd.) seeks a Linux Hacker & Nix Wizard (Senior/Expert) to join our Kraków team. You will tackle Linux internals, memory management, IPC, and system calls, while optimizing Python performance and enabling Nix/NixOS configurations.

You should have fluent English, strong problem-solving skills, and a hands-on, ownership-driven mindset to work on reproducible builds and advanced diagnostics in a fast-growing tech environment.

Qualifications

• Deep, hacker-level knowledge of Linux internals, memory management, IPC, and system calls.
• Expert-level mastery of Python (performance optimisation, async execution, C/Rust interop).
• Hands-on expertise with Nix / NixOS or strong mastery of declarative system configuration & reproducible builds.

Skills

Linux internals

Nix/NixOS

Python

English (C1)

System architecture

Self-driven

Job description

We are #VLteam - tech enthusiasts constantly striving for growth. The team is our foundation, that's why we care the most about the friendly atmosphere, a lot of self-development opportunities and good working conditions (yes, that also means attractive salaries). Trust and autonomy are two essential qualities that drive our performance. We simply believe in the idea of “measuring outcomes, not hours”. Join us & see for yourself!

Linux Hacker & Nix Wizard

Details: Linux Hacker & Nix Wizard (Senior / Expert)

Required skills:

Linux Core or Low-Level Linux Kernel Internals - Advanced

Nix - Advanced / Regular

Python Programming- Expert

English Communication: C1 - Advanced

System Architecture & Automation - Advanced

Self-driven & Problem Solving - Advanced

Desired professional profile & core competencies:

• Deep, hacker-level understanding of Linux internals, memory management, IPC, and system calls.
• Expert-level mastery of Python (performance optimisation, async execution, C/Rust interop).
• Hands-on expertise with Nix / NixOS or strong mastery of declarative system configuration & reproducible builds.
• Advanced experience with low-level kernel diagnostics and profiling (eBPF, perf, strace, valgrind).
• Fluent command of spoken and written English.
• Uncompromising ownership, analytical rigour, and a natural instinct for deep technical problem-solving.