📍 Location: Madrid, Spain (3 days/week onsite in city center)🌍 Eligibility: EU Citizens or Candidates with a Valid European Work VisaAbout the Role:UST is looking for a Senior Software Engineer with strong expertise in Java and Cloud-native platforms. As a Senior Software Engineer, you’ll take technical ownership of critical systems and drive architectural direction across multiple teams. In our agile, DevOps - centric environment, you’ll lead the end-to-end lifecycle of high-impact services- shaping design, delivery, and operations - while mentoring engineering leads and influencing best practices at scale.Key Responsibilities:Technical Strategy amp; Architecture: define and evolve the architecture for large-scale, microservices-based systems: Lead cross-team design reviews, ensuring alignment with performance, security, and scalability goals.DevOps amp; Delivery Excellence: Architect and optimize CI/CD pipelines for complex, multi-team workflows. Champion observability, resilience, and “everything as code” across infrastructure and deployments.Feature Leadership amp; Stakeholder Partnership: Own the delivery of major features, coordinating with Product, UX, and Operations to meet business objectives. Act as a senior technical liaison for stakeholders, translating strategic goals into actionable roadmaps.Quality amp; Engineering Standards: Establish and enforce coding standards, testing requirements (TDD/BDD), and performance benchmarks. o Introduce and evangelize new tools, frameworks, and processes that elevate team productivity and code quality.Mentorship amp; Organizational Impact: Mentor senior and mid-level engineers—guiding career growth, architectural thinking, and technical decision-making. o Lead brown-bags, hackathons, and guild meetings to foster a culture of continuous learning and innovation.Mandatory Requirements:9 - 12+ years building and scaling distributed systems in agile/DevOps organizations.Expert in Java, Spring Boot, RESTful microservices, and event-driven architectures (Kafka, Avro).Strong frontend acumen with React, JavaScript/TypeScript, and API-first integration (OpenAPI).Deep familiarity with Kubernetes orchestration, container security, and infrastructure as code.English level: C1 (professional fluency).What We Offer:Annual Leave: 23 days + 24th and 31st December as discretionary holidays.Flexible Compensation Options: Meals, transport, kindergarten, online English lessons, and more.Work-Life Balance: Remote/hybrid model, flexible hours, and compacted summer schedules.Relocation Package: will be covered by the company side.Employee Benefits: Private health insurance, accident insurance, and connectivity support.Training Access: Free access to leading training platforms and continuous learning opportunities.Referral Bonuses: Earn rewards when you refer qualified professionals.Salary Payment Choice: Opt between 12 or 14 payments annually.Wellbeing Extras: Discounts on gyms and UST Club partner deals.Inclusion amp; Diversity at USTWe believe in equal opportunities and encourage applications from all backgrounds. We are especially committed to hiring individuals with a disability certificate as part of our inclusion goals.