This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Userplane Protocol Stack Engineer based in Spain. This role is ideal for an experienced networking engineer passionate about building and optimizing modern communication systems.You will contribute to the development of protocol-driven solutions supporting secure, scalable, and high-performance network environments.The position requires deep knowledge of networking concepts, cloud infrastructure, and distributed systems architecture.You will work with technologies such as TCP/IP protocols, Kubernetes, cloud platforms, and microservices to solve complex engineering challenges.Your expertise will help improve connectivity, reliability, and performance across advanced software environments.This is an opportunity to join a technically driven team where your networking skills and engineering experience create measurable impact.