Lead Server-side Engineer (Java)

We are looking for a Lead Server-side Engineer to build and evolve a high-scale Backend for Frontend service layer for mobile experiences used by tens of millions of cardholders worldwide. You will lead design and delivery with a cross-functional team, prioritize performance and code quality, and help shape technical direction. Apply to join us. Responsibilities Design the Backend for Frontend architecture for mobile-facing APIs Lead technical decisions and mentor engineers on best practices and code quality Build server-side services in Java using Spring Boot Define and implement REST API contracts that support excellent client experiences Write unit tests and enforce reliable automated test coverage Optimize latency, throughput, and resource usage through performance analysis Coordinate delivery with product, design, and QA to meet quality and timeline goals Refactor legacy code to improve maintainability, readability, and safety Fix production issues by debugging, triaging, and implementing robust solutions Integrate with existing backend services, including bespoke legacy systems Improve CI and build pipelines to increase delivery speed and confidence Review code and promote clean, elegant, and secure implementations Requirements 5+ years of Java backend development experience Strong leadership skills in guiding engineers and technical decision-making Proven project delivery experience in cross-functional teams with product, design, and QA Advanced Spring Boot knowledge for building server-side applications Strong REST API design skills for mobile-facing service layers Solid algorithms and data structures knowledge for solving complex problems Strong unit testing skills and test-driven development mindset Hands-on performance analysis and optimization skills for high-traffic services Experience with CI and build tools in modern engineering workflows Strong problem-solving skills for open-ended solution design and legacy integrations Clear communication skills and willingness to share ideas and drive alignment Bachelor’s degree in Computer Science or related field, or equivalent experience English Upper-Intermediate (B2) proficiency Nice to have Docker for local development and service packaging Gradle for build configuration and dependency management GraphQL for API schema design and query optimization Kotlin for JVM-based backend development RAML for API modeling and documentation