Senior Backend Engineer

WEX is a global leader in financial technology solutions, simplifying complex payment ecosystems across Fleet, Corporate Payments, and Health \& Benefits. For further details, please visit www.wexinc.com. We are driving a major technology transformation to modernize our platforms, accelerate innovation, and deliver exceptional customer experiences. **About The Role:** We are seeking a Senior Software Engineer who can design and deliver scalable, secure, and modular systems that align with our technology transformation strategies. As part of this team you will have the opportunity to build scalable high impacting services and also modernize our legacy services by building modular, scalable microservices using modern technologies across the entire architecture. These systems are designed to be highly available, resilient, easy to maintain, developer\-friendly, and optimized for performance without dependency on legacy components. **How you’ll make an impact:*** Lead the design and development of full\-stack solutions, with emphasis on event\-driven microservices, APIs, and data platforms * Drive iterative modernization by decomposing monoliths into shared, modular services * Build reusable capabilities aligned with product\-centric domain models * Contribute to agentic architectures and intelligent automation that power seamless user experiences * Collaborate with cross\-functional teams to deliver measurable business outcomes, not just features * Mentor junior developers and promote best engineering practices **Experience you'll bring:*** Design, develop, test, and maintain cloud\-ready microservices and APIs * Work with streaming data pipelines (Kafka) to enable real\-time insights * Apply platform\-thinking approaches by building reusable and discoverable capabilities * Ensure quality from the start through automated validation and CI/CD pipelines * Deliver value iteratively, focusing on finishing and deploying features * Partner with product and architecture teams to ensure systems are decoupled, scalable, and SaaS\-mature * Use monitoring and feedback loops to drive data\-informed improvements * Proactively tackle technical debt while balancing modernization and customer value delivery **Preferred Qualifications:*** Bachelor’s or Master’s degree in Computer Science or Engineering * Experience in backend or microservices development (Java, .NET, Python, Go, etc.) * Hands\-on experience with Java and Java\-based frameworks * Expertise in object\-oriented design and programming * Strong problem\-solving skills in the software engineering domain * Experience working with modern backend microservices architectures * Experience building and consuming RESTful APIs * Experience with message brokers and event\-streaming platforms (Kafka) * Strong knowledge of SQL, relational, and non\-relational databases * Comfort working with JSON, XML, YAML, and other interface file formats * Experience with Unix/Linux environments, scripting, and CI/CD pipelines * Demonstrated ability to decompose systems into modular, reusable services * Excellent communication and collaboration skills across distributed teams **Nice to Have*** Experience with FinTech solutions or payments ecosystems * Cloud experience (AWS preferred) and containerization (Docker, Kubernetes) * Familiarity with modern UI frameworks (React, Angular, Vue.js) * Experience with Change Data Capture (CDC) tools * Understanding of AI/ML integration in platforms and workflows * Experience with large\-scale transactions and highly available systems **What Makes You a Great Fit*** You embody our engineering principles: API\-first, modular, iterative, and data\-driven * You thrive in modernization work, making legacy systems more agile You value finishing and delivering over just starting * You see engineering as a way to unlock business outcomes, not just write code You champion quality, automation, and reusability in everything you build