Remote Senior Full-Stack Engineer - Backend & APIs

WEX, Inc.; Seattle (WA); Remote; USD 122,000 - 146,000; Full time

Benefits offered by this job

Health insurance

Dental and vision insurance

Retirement savings plan

Paid time off

Health savings account

Flexible spending accounts

Life insurance

Disability insurance

Tuition reimbursement

Job summary

WEX, Inc. is seeking a Senior Software Engineer for a remote role with a requirement to reside within 30 miles of Seattle.

You will contribute to the Beyond Fuel and Expense Management initiative, shaping architecture and engineering practices across web, mobile, and backend services. You will design APIs, build scalable services, and partner with Product, Security, and Design to deliver secure, reliable payment and expense management experiences.

Qualifications

• Bachelor's degree in Computer Science, Software Engineering, or a related field.
• 6-8 years of professional software engineering experience.
• 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.
• Strong communication skills to collaborate effectively across multidisciplinary teams.
• Ability to explain technical decisions clearly to engineering and business stakeholders.
• A track record of mentoring engineers and improving engineering practices through hands‑on collaboration.
• Hands‑on experience leveraging AI coding assistants and development tools to accelerate software development, refactoring, and code generation.

Responsibilities

• Contribute to 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.
• Participate in design reviews, code reviews, and technical discussions to support engineering quality.
• 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.

Skills

Java

Spring Boot

Backend architecture

Distributed systems

REST API design

Education

Bachelor's degree

Tools

GitHub Copilot

Cursor

Claude

Job description

WEX, Inc. is seeking a Senior Software Engineer for a remote role with a requirement to reside within 30 miles of Seattle.

You will contribute to the Beyond Fuel and Expense Management initiative, shaping architecture and engineering practices across web, mobile, and backend services. You will design APIs, build scalable services, and partner with Product, Security, and Design to deliver secure, reliable payment and expense management experiences.