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July 14, 2026

C# Developer – Firmware & Hardware Interfaces (f/m/x)

Senior • Remote

Wrocław, Poland

We are looking for an experienced C# Developer with a strong background in low-level development and hardware integration to join Sii and contribute to an innovative project delivered for our client — an international company operating in the AI-driven investment technology domain. You’ll work in a fully remote, startup-like environment, building solutions that combine software engineering with machine-level interaction and firmware communication. This is a great opportunity to grow within distributed teams and modern engineering practices, including CI/CD and Agile delivery models.

At Sii, we support continuous development and offer access to diverse projects aligned with your expertise.

If you like getting close to the hardware, enjoy solving complex integration challenges, and want to see how your code interacts with real-world systems — this project is for you. Apply now and build solutions where software meets machines. Not a 100% match? Let’s talk anyway — we’ll match you with the right opportunity.

Your tasks

  • Develop and maintain C# applications interacting with hardware components and low-level systems

  • Design and implement interfaces for communication with machine control layers and embedded components

  • Integrate software solutions with firmware and ensure reliable data exchange between layers

  • Collaborate with cross-functional, distributed teams in an Agile environment using CI/CD pipelines

  • Participate in code reviews, testing, and continuous improvement of system performance and reliability

Requirements

  • Minimum 5 years of experience as a C# Developer or in a similar role

  • Hands-on experience with low-level or machine-oriented development and hardware interaction

  • Strong knowledge of firmware interfacing and control layer communication

  • Practical experience with Agile methodologies and CI/CD processes (GitHub/GitLab)

  • English proficiency at min. B2 level (comfortable working in an international environment)

Nice-to-have requirements

  • Experience working in a SAFe environment

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