Software Development Engineer 4

About the Team/Role We are seeking a Staff Software Engineer in the WEX Mobility Engineering organization. This role will sit in the North America Mobility team, which delivers fleet management and mobility payments solutions to large customers and partners across North America. The Mobility development organization spans the United States, Brazil, and India. Our Mobility systems provide SaaS and API solutions to customers and partners. Mobility products enable credit issuance to fleet companies and their workers through WEX and cobranded credit cards, usable at fueling stations and select other merchants. We provide fleet managers and operators with fuel discounts and flexible spend controls that restrict fleet members to configured merchants, amounts, and transaction velocity. As a Staff Software Engineer, you will provide deep technical leadership across multiple teams and services. You will solve architectural problems that cross team boundaries, establish reusable engineering patterns, and align technology decisions with customer and business outcomes. You will remain hands-on in foundational and technically difficult areas while enabling other engineers and teams to deliver safely and quickly. How you’ll make an impact: Define and evolve architecture across multiple Mobility services, identifying and resolving bottlenecks that cross team boundaries. Lead architecture reviews and technical workshops with engineering, product, security, compliance, operations, and partner teams to align on complex flows and long-term direction. Establish golden paths, reference architectures, and reusable libraries or frameworks for APIs, service communication, event-driven integrations, data access, observability, and cloud infrastructure. Set technical standards for public REST APIs, internal gRPC APIs, service contracts, versioning, compatibility, and integration patterns using Java, Spring Boot, ODATA, SQL, and related technologies. Design secure, scalable, highly available, and resilient internet-scale systems for fleet management and mobility payments, balancing customer experience, cost, performance, and operational risk. Lead security-by-design and compliance-by-design practices, including threat modeling, API security, authorization standards, PCI DSS considerations, data protection, and auditability across multiple teams. Define common SLIs, SLOs, operational readiness expectations, and observability standards; drive chaos testing and resilience improvements across critical services. Identify recurring classes of defects, reliability issues, and operational toil across services, then drive systemic fixes rather than isolated patches. Create reusable CI/CD and infrastructure-as-code patterns, such as standardized Helm charts, Argo workflows, Terraform modules, and secure cloud resource templates, to improve delivery speed and consistency. Set organizational expectations for code quality, testing strategy, maintainability, and production behavior. Select or influence testing frameworks and promote effective unit, integration, contract, end-to-end, concurrency, and performance testing. Code selectively in foundational, high-risk, or technically challenging components; use prototypes and technical spikes to validate architecture before broad adoption. Debug complex issues across service boundaries, lead technical resolution during major incidents, and drive completion of Corrective of Errors (COE) actions and lasting reliability improvements. Build self-service tools, dashboards, and automation that enable engineers, support teams, and operational partners to diagnose and resolve issues without manual intervention. Shape cross-team roadmaps by identifying dependencies, critical-path risks, architectural constraints, and opportunities to reduce technical debt before they affect delivery. Translate architectural risks and technology investments into business language, connecting decisions to customer experience, revenue, retention, operational efficiency, and risk reduction. Mentor senior engineers, advocate for the growth and visibility of engineers across the organization, and build a culture of thoughtful technical decision-making and inclusive collaboration. Evaluate emerging technologies through cost-benefit analysis; build safe adoption paths for high-value technologies and coach teams through technical transitions. Leverage AI-enabled development tools and design responsible AI solutions, including multi-agent workflows, orchestration, state and memory management, evaluation, safety controls, and production integrations where they create measurable value. Maintain durable documentation, including architecture decision records, design documents, reference implementations, runbooks, COE documents, change-management plans, and operational-readiness plans. Experience you’ll bring: Bachelor’s degree in Computer Science, Software Engineering, or a related field. 7-12 years of professional software engineering experience, including demonstrated technical leadership across multiple teams or systems. Deep understanding of data structures and algorithms, object-oriented design, distributed systems, and complex problem solving. Proven experience designing and evolving internet-scale services with strong scalability, availability, security, reliability, and operability characteristics. Strong written and verbal communication skills, with the ability to build alignment among technical and non-technical stakeholders. Expertise in backend development using Java or C#, with frameworks such as Spring Boot; strong experience building and optimizing RESTful APIs, ODATA services, gRPC interfaces, and SQL-based systems. Experience defining service boundaries, integration contracts, platform patterns, and architecture standards used by multiple teams. Experience with event-driven architecture and technologies such as Kafka, cloud-native architecture, Docker, Kubernetes, and infrastructure as code. Experience establishing observability, SLI/SLO, incident-management, resilience-testing, and production-readiness practices. Experience with secure API design, threat modeling, compliance-by-design, and PCI DSS or other regulated payment environments. Ability to leverage AI-enabled development tools such as Cursor AI, Kiro, and GitHub Copilot to accelerate delivery, automate documentation, improve code quality, and coach other engineers in secure adoption. Experience designing or deploying production-grade AI agents, copilots, multi-agent systems, or distributed AI architectures; familiarity with vector databases and AI evaluation, safety, and responsible-AI practices. Preferred Qualifications Master’s degree in Computer Science, Software Engineering, or a related field. Experience in card payments, fleet management, mobility, or other financial technology domains. Experience with mobile development on iOS or Android. Experience leading organization-wide or multi-team platform, modernization, or reliability initiatives. Experience creating internal developer platforms, golden paths, reusable frameworks, or engineering standards adopted by multiple teams. Experience building AI skills and deploying AI solutions to production environments. Familiarity with vector databases such as Pinecone, Weaviate, OpenSearch, or Milvus. Knowledge of AI evaluation techniques, safety practices, governance, and responsible AI principles.