Senior Full Stack 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, ME.

About the Team/Role

WEX is a global leader in financial technology solutions, simplifying complex payment ecosystems across Fleet, Corporate Payments, and Benefits. We are driving a major transformation through Helix—a technology strategy to modernize our platforms, accelerate innovation, and deliver exceptional customer experiences.
 

We are seeking a Full Stack Software Engineer (Level 3) who can design and deliver scalable, secure, and modular systems that align with Helix’s pillars: workflow optimization, payments intelligence, and industry expertise. This role offers the opportunity to shape our next-generation platforms while modernizing legacy systems into API-first, composable, and data-driven architectures.

How You’ll Make an Impact

• Lead design and development of full-stack solutions, with emphasis on event-driven microservices, APIs, and data platforms.

• Drive iterative modernization, helping decompose 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 Helix-aligned engineering practices.

What You’ll Do

• Design, develop, test, and maintain cloud-ready services and APIs.

• Work with streaming data pipelines (Kafka, CDC, JSON) to enable real-time insights.

• Implement platform-thinking approaches—build reusable, discoverable capabilities.

• Ensure quality from the start through automated validation and CI/CD pipelines.

• Deliver value iteratively, focusing on finishing and deploying features, not just starting them.

• 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.

• Tackle technical debt proactively, balancing modernization with customer value delivery.
   

Experience You’ll Bring

• Bachelor’s degree in Computer Science, Engineering, or equivalent experience.

• 5+ years in backend/microservices development (Python, Java, Node.js, etc).

• 3+ years building RESTful APIs; experience with event streaming (Kafka).

• Strong knowledge of CDC, JSON/XML, relational/NoSQL, Postgres and other modern databases.

• Experience in 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 platforms or payments ecosystems.

• Exposure to Siebel CRM or other enterprise systems, particularly in integration.

• Cloud experience (AWS preferred), containerization (Docker, Kubernetes).

• Familiarity with modern UI frameworks (React, Angular, Vue.js).

• Understanding of AI/ML integration in platforms and workflows.

• Experience with large-scale transaction or high-availability systems.

What Makes You a Great Fit

• You embody Helix principles: API-first, modular, iterative, 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.

The base pay range represents the anticipated low and high end of the pay range for this position. Actual pay rates will vary and will be based on various factors, such as your qualifications, skills, competencies, and proficiency for the role. Base pay is one component of WEX's total compensation package. Most sales positions are eligible for commission under the terms of an applicable plan. Non-sales roles are typically eligible for a quarterly or annual bonus based on their role and applicable plan. WEX's comprehensive and market competitive benefits are designed to support your personal and professional well-being. Benefits include health, dental and vision insurances, retirement savings plan, paid time off, health savings account, flexible spending accounts, life insurance, disability insurance, tuition reimbursement, and more. For more information, check out the "About Us" section.Pay Range: $120,000.00 - $160,000.00