Senior Backend Engineer: Machine Learning Infrastructure

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Backend Engineer: Machine Learning Infrastructure based in Spain. As a Senior Backend Engineer, you’ll help build the infrastructure that enables machine learning teams to develop, deploy, and operate models reliably at scale. You’ll own critical backend services, data pipelines, and platform capabilities supporting workloads ranging from traditional machine learning to LLMs. The role combines distributed systems engineering, cloud infrastructure, API development, observability, and platform design. You’ll work closely with ML and product teams to understand their needs and turn them into reusable, self-service infrastructure. You’ll have significant autonomy to make technical decisions, evaluate trade-offs, and take solutions from design through continuous improvement. The environment is remote-first, collaborative, and strongly oriented toward ownership, thoughtful engineering, and modern AI-assisted development. This is an opportunity to have a direct impact on how teams build and operate machine learning products at scale.