System Test Engineer

About Stellar  Stellar brings together professionals and experts from a range of exciting domains and technologies: telecommunications (cellular 4G/5G terrestrial and non-terrestrial networks, Wi-Fi and satellites), mobility (trains, aircraft, drones and road vehicles), and software for efficient data transmission, orchestration, network management, data collection, processing and analysis, including growing AI/ML capabilities.  Our products and solutions - the STEER® Software Suite, M2M/IoT solutions and the all-in-one GLOBBLE® offering - are transforming how people and vehicles experience connectivity while on the move by enabling seamless, ubiquitous and reliable broadband services. More information is available at https://www.stellar.tc.  Stellar is an ideal workplace for professionals who are eager to learn, challenge conventional approaches, explore practical innovations and take meaningful ownership in a supportive, collaborative, results-driven, international and professional environment. Position Summary  Reporting to the Director of Software Development, the System Test Engineer focuses on Quality Assurance (QA) within the Stellar team, ensuring our software modules and architecture meet the highest standards of performance, quality, security, and reliability. Working closely with the STEER EDGE & Gateway, STEER Management, and DevOps stakeholders, you will carry out integration, system-level and performance testing across telecommunications and mobility use cases, spanning embedded devices, on-premises platforms and remote environments. Unit and functional testing is handled by the development teams; this role validates the complete, assembled system. Key Responsibilities Design and execute comprehensive test strategies to ensure the quality and correct behaviour of software and hardware modules. Test STEER EDGE and STEER Gateway software on GLOBBLE® hardware platforms, including multipath networking, VPN, and firmware update scenarios. Validate STEER Management releases (Django/OpenWisp) at the system level across dev, QA, and production environments, in coordination with the DevOps and STEER Management teams. Plan and execute field trials of GLOBBLE® units across varied network conditions and deployment environments. Implement and maintain automated testing frameworks to streamline the QA process. Verify that test environments meet the resource and configuration specifications required for valid results before starting a validation campaign. Structure and maintain automated test-reporting tooling (e.g. the existing GitLab-based Python reporting scripts), and help other team members adopt a repeatable test methodology. Identify, document, and track software defects, collaborating with developers for swift resolution. Conduct a full range of testing, including field trials, to validate software stability and performance across real-world deployment conditions. Collaborate with cross-functional teams to define and uphold QA standards. Review and provide feedback on software requirements, design documents, operational procedures to ensure testability and quality. Produce formal test documentation and validation reports, either for internal purposes or to satisfy customers’ project milestones. Drive continuous improvement of QA processes, incorporating Agile and DevOps best practices. Required Experience and Skills 3+ years of hands-on experience in software or systems testing, ideally in embedded, networking, or telecommunications environments. Strong understanding of networking fundamentals (TCP/IP, VPN, routing, NFTables and similar tools) and Linux systems (ideally, Debian), including ability to analyze and interpret system/network logs (e.g., dmesg, journalctl, syslog, daemon/service logs, tcpdump traces) to isolate root causes and diagnose failure modes. Experience designing and maintaining automated test suites and frameworks, ideally in Python and Shell scripting. Comfortable working hands-on with physical hardware for field trials and hardware-in-the-loop testing. Proven ability to write clear, actionable bug reports with reliable, step-by-step reproduction steps, root-cause details, logs, and system context. Familiarity with CI/CD tooling (e.g. Jira, GitLab CI). Experience writing formal test plans, results and documentation. This may include deliverables to customers. Rigorous, methodical approach to documentation and reporting. Professional proficiency in English (French a plus). Preferred Experience Experience testing OpenWrt-based or embedded Linux devices. Hands-on experience isolating network traffic or simulating multi-node environments on single-board targets using Linux network namespaces. Familiarity with Django/Python-based web platforms, Robot Framework and Selenium or similar browser-automation tools Experience with multipath networking and VPN technologies. Experience in telecommunications, satellite, or mobility connectivity products. What We Offer Strong ownership over the quality and reliability of Stellar's software and hardware stack. Hands-on exposure to a wide range of technologies: embedded Linux, advanced networking, hardware integration, AI to support your activities, etc. Continuous learning in a supportive, expert-driven engineering team. A collaborative, international and multicultural working environment. A competitive compensation package, including Stellar stock options. Your profile is not a 100% match with the description above, but you are interested in our project? No worries, apply anyway. We are primarily looking for people with the right mindset who are willing to learn.