Senior Java Developer, Applications Development

Citi is looking for a Senior Java Developer to join its Applications Development team, where you will design, build, and own high-performance Java applications that underpin critical financial services at global scale. This is a hands‑on technical role where your expertise will directly shape the quality, architecture, and reliability of systems that process high-volume, latency-sensitive workloads. If you are an engineer who takes full ownership of what you build and thrives in a fast-moving, technically demanding environment, this is the role for you.

Responsibilities

• Design and develop efficient, reusable, and reliable Java code for high-volume, low-latency applications, setting the benchmark for engineering quality across the team.
• Architect RESTful APIs and scalable backend services using Spring and Spring Boot, ensuring optimal performance, responsiveness, and maintainability from day one.
• Translate complex business and user requirements into detailed technical specifications, low-level design documents, and solution architecture artefacts.
• Identify, evaluate, and champion the adoption of emerging technologies and frameworks that meaningfully enhance the application stack.
• Build and maintain comprehensive testing automation - covering unit, integration, and performance tests - to uphold code quality and production reliability.
• Lead peer code reviews, providing precise and constructive feedback that raises engineering standards across the team.
• Take full accountability for production systems, including rapid diagnosis and resolution of critical issues to minimise customer and business impact.
• Partner with business analysts, project managers, and senior engineers across functions to deliver high-quality software, while establishing and maintaining clear standards for technical documentation.

Required Qualifications & Skills

• 5 or more years of professional Java development experience, with substantial exposure to cloud-based environments and distributed systems.
• Expert-level command of Java, RESTful API design, and cloud engineering principles, with hands‑on experience building production‑grade services using Spring and Spring Boot.
• Solid database experience spanning relational systems such as Oracle and SQL, as well as NoSQL technologies including MongoDB.
• Practical experience with cloud-native platforms including OpenShift and Kubernetes, and messaging technologies such as MQ and Kafka.
• Deep commitment to clean code principles, design patterns, and test‑driven development practices that produce maintainable, production‑ready software.
• Fluency in Agile methodologies and the full software development lifecycle, with hands‑on experience building and maintaining CI/CD pipelines using DevOps tooling.
• Demonstrated ability to lead technical delivery autonomously, manage competing priorities, and perform effectively under pressure in a fast‑paced environment.

Beneficial Skills & Qualifications

• Background in financial services with a focus on payments processing, giving you immediate context for the systems you will be building.
• Familiarity with Generative AI and large language models, and an interest in applying these technologies within an enterprise engineering context.
• Experience designing integration patterns between mainframe systems and modern event-driven or API-based architectures using Kafka.
• Recognised depth of expertise as a subject matter expert in at least one critical area of applications development.

What We Offer

At Citi, you will work on systems that matter — at a scale few organisations can match. Our Applications Development teams operate at the intersection of engineering excellence and real-world financial impact, giving you the technical complexity, cross‑functional collaboration, and career depth to grow as an engineer and leader. We support your professional and personal wellbeing with a benefits package designed to deliver long-term value.

• Hybrid working model with 3 days in the office and 2 days working remotely, giving you the structure of in‑person collaboration and the flexibility of remote work.
• Exposure to globally significant, technically complex systems across one of the world's leading financial institutions.
• Ongoing learning and development opportunities, including access to technical training, architectural review processes, and cross‑team knowledge sharing.
• A performance‑driven environment where engineers are empowered to make meaningful technical decisions and take ownership of outcomes.
• Competitive compensation and financial wellbeing support, including access to Citi's broader benefits programme tailored to your location.
• Wellbeing and work‑li