Java Backend Developer

Join our TPA Dev team in Madrid and grow into a Calypso Developer. You'll start as a seasoned Java backend engineer and receive structured training on Calypso, used for Triparty Collateral Management and Repo Services at SIX. This is an on-the-job learning path: you'll build production-grade services while deepening your knowledge of Calypso and the post-trade domain. What You Will Do

• Design, build, and operate backend services in Java for collateral management and repo workflows, evolving into Calypso customizations and integrations.
• Develop robust, multi-threaded services and APIs using Java 8+ and Spring Boot; expose and consume RESTful interfaces.
• Implement event-driven integrations (e.g., messaging/streaming) between Calypso and internal/external systems.
• Model, optimize, and maintain relational data structures; write efficient SQL and work with ORM frameworks (Hibernate/JPA).
• Contribute to solution design and architecture, ensuring scalability, resiliency, and observability across services.
• Collaborate closely with business analysts, Calypso specialists, and SRE/DevOps to deliver reliable, compliant, and secure solutions.
• Participate in the full SDLC: requirements, estimation, implementation, code reviews, testing (unit/integration), deployment, and production support.
• Embrace infrastructure and platform standards (e.g., Linux RHEL 8+, containerization, CI/CD) and help automate build/test/deploy pipelines.
• Learn and extend Calypso: configuration, workflows, data models, APIs, and custom components to support triparty collateral and repo processes.
• Contribute to continuous improvement: reduce technical debt, improve system performance, strengthen security, and enhance developer productivit, Diversity is important to us. Therefore, we are looking to receiving applications regardless of any personal background. What We Offer Flexible Work Models We trust our employees and offer a work environment that is well-balanced, productive and fosters success. Personal Development You will benefit from a culture of continuous learning and feedback. Your personal growth is supported through an extensive learning offering. Agile Working Methods Whether through scrum or design thinking, we solve exciting tasks together in teams.

• 4+ years of hands-on software engineering experience with a strong focus on multithreaded backend development in Java (Java 8+).
• Proficiency with Spring Boot, RESTful API design, and building reliable distributed services.
• Strong database skills: SQL expertise, sound schema design, and experience with Hibernate/JPA.
• Solid understanding of object-oriented design, event-driven architectures, and messaging patterns.
• Familiarity with Linux environments (RHEL 8+), and comfort working with modern CI/CD practices and tooling.
• Understanding of financial markets and post-trade infrastructure; exposure to collateral or repo is a plus.
• Growth mindset: positive, result-driven, quality-focused, and systematic thinker with a problem-solving attitude.
• Collaborative communicator, team-oriented, resilient under pressure; ability to work in a cross-functional, multicultural environment.
• Language skills: English required; German and/or Spanish are a plus.

SIX Group Ver todas las vacantes * Madrid * Permanente * Tiempo completo * Hace 2 horas BME - Bolsas y Mercados Españoles - drives the transformation of financial markets and belongs to SIX, the third largest exchange group in Europe. What sets us apart drives us ahead: between local roots and global relevance, we are a unique blend of tradition and future, of foundation and growth. We value bright minds and inspire them to grow with their ideas. Come and shape the future of finance with us.