Freelance Project Opportunity – Senior Software Engineer (Madrid, Hybrid) We are looking for a Senior Software Engineer to join a freelance project in Madrid. This is a hybrid role with regular on‑site work required. Key Skills & Experience: Strong background in C/C++ development for embedded systems Proficiency in Linux Experience in software design & architecture for real‑time sensor applications Knowledge of CI/CD processes and version control Familiarity with SoC platforms Ability to analyze and refactor legacy C++ code Experience with API design & development (REST, ONVIF, CGI) Strong knowledge of internal protocols : MQTT, serial communication, sockets Location: Madrid (Hybrid, regular on‑site presence)