Senior Software Engineer

Senior Software Engineer – Madrid X3 Staff Software Engineer X1 📍 Madrid, Spain | Hybrid – 1 day per week on-site / 4 days working from home 💰 €70,000–€90,000 gross annual salary + bonus We are working with a fast-growing international SaaS and finance business that is scaling its engineering team in Madrid. As part of this growth, the company is looking to hire 3 Senior Software Engineers and 1 Staff Software Engineer to join its expanding technology function. This is an exciting opportunity to join an international engineering environment where you will work on a highly scalable SaaS platform, taking ownership of backend services and contributing to architecture, product development and technical improvements. The role is hands-on and suited to an experienced engineer who combines strong Java and Spring Boot expertise with good engineering judgement, product thinking and a commitment to building secure, reliable and maintainable software. Key responsibilities - Design, build and maintain scalable services using Java, Spring Boot - Own features and services from technical design through deployment and production operation. - Translate product requirements into pragmatic, maintainable technical solutions. - Design REST APIs, data models and asynchronous integrations for a multi-tenant SaaS platform. - Contribute to architectural decisions and constructively challenge proposals where risks or better alternatives are identified. - Write clean, secure and well-tested code. - Participate actively in code and design reviews. - Improve platform reliability, performance, observability and maintainability. - Diagnose production issues, identify root causes and implement lasting improvements. - Help modernise existing services and manage technical debt. - Use AI-assisted development tools responsibly to improve development, testing, documentation and problem-solving. - Share knowledge and support the development of other engineers. - Collaborate closely with Product Managers, QA Engineers and wider technical teams. Experience required - 4+ years of professional software engineering experience, including ownership of production backend systems. - Strong hands-on experience with Java and Spring Boot - Experience designing and consuming RESTful APIs. - Strong knowledge of relational databases, data modelling and SQL. - Hands-on experience with JavaScript and React. - Solid understanding of modern front-end development practices and component-based architectures. - Experience with automated unit, integration and API testing. - Experience with Git, code review and CI/CD practices. Nice to have - Experience with AWS and cloud-native applications. - Experience with Docker and Kubernetes. - Knowledge of microservice and modular monolith architectures. - Experience with event-driven systems, Kafka or AWS SQS. - Experience with MongoDB or other non-relational databases. - Knowledge of observability, monitoring, alerting and incident response. What’s on offer? - €70,000–€90,000 gross annual base salary, depending on experience and technical knowledge. - Bonus scheme. - 25 days' holiday + your birthday off. - Employee share option scheme. - Flexible working and a hybrid working model – just 1 day per week on-site in Madrid and 4 days working from home. - Flexible perks package. - Opportunity to join an international business with teams across Spain and the UK. - Diverse, inclusive and collaborative working environment. - The opportunity to work on an innovative SaaS platform within the embedded finance/fintech space. Apply now or get in touch for a confidential conversation.