Software Engineer, Backend Developer, Full Stack Developer

Position: Staff Software Engineer
This is a remote position; however, the candidate must reside within 30 miles of one of the following locations:
Boston, MA;
San Francisco Bay Area, CA;
Dallas, TX;
Salt Lake City, UT;
Seattle, WA; and Portland, MEAbout the Team/Role Are you excited about building solutions that expand fleet payments beyond fuel and simplify expense management? We are seeking a Full-stack Staff Software Engineer with deep expertise in backend development to provide technical leadership for the WEX Beyond Fuel and Expense Management initiative within WEX Mobility Engineering.

This is a brand-new initiative, offering the opportunity to shape the architecture, establish engineering practices, and build the product from initial design through production launch. You will work across web & mobile applications, backend services, APIs, and partner integrations to deliver secure, reliable, and scalable payment and expense management experiences.

This is an individual contributor role with technical leadership responsibilities and no direct people management. You will remain hands-on while guiding technical decisions, mentoring engineers, and collaborating with Product, Design, Security, and engineering teams across the United States and India.​How you’ll make an impact:

Lead the technical architecture, design, and implementation of the Beyond Fuel and Expense Management platform.

Build full-stack capabilities spanning user interfaces, backend services, data models, and external integrations.

Translate product requirements into technical designs, delivery milestones, and implementation plans.

Design reusable business capabilities and APIs that support web, mobile, and partner experiences.

Establish patterns for payment workflows, expense capture, approvals, spend controls, transaction reporting, and reconciliation.

Evaluate technical options and communicate tradeoffs involving performance, security, reliability, cost, and delivery timelines.

Write production code, review contributions, and resolve complex issues across the application stack.

Guide engineers through design reviews, code reviews, technical mentoring, and collaborative problem-solving.

Establish standards for automated testing, API contracts, observability, accessibility, and secure development.

Build production readiness into the product through actionable logs, distributed tracing, metrics, dashboards, and alerts.

Use approved AI tools throughout development, testing, and documentation, and review and validate all generated output.

Partner with engineering leaders to identify dependencies, manage technical risks, and support delivery.

Own technical outcomes from initial implementation through deployment, operation, and continuous improvement.

Experience you'll bring

Bachelor's degree in Computer Science, Software Engineering, or a related field.
8–10 years of professional software engineering experience.

Experience taking a new product from concept to production and evolving it as adoption grows.

Strong proficiency in Java and Spring Boot, or comparable backend technologies.

Strong understanding of object-oriented design, data structures, algorithms, and software design principles.

Experience designing REST APIs, distributed systems, relational data models, and event-driven integrations.

Experience with cloud platforms, preferably AWS, and automated CI/CD pipelines.

Knowledge of authentication, authorization, data protection, and secure API design.

Experience with unit, integration, end-to-end, and performance testing.

Experience building and operating production services with monitoring, distributed tracing, and incident troubleshooting.

Ability to influence technical direction across teams without formal management authority.

Ability to explain technical decisions…