Staff Software Development Engineer – Agentic Applications and Experiences

Portland, ME · Chicago, IL · Seattle, WA · Dallas, TXFull-time$141k–$173kPosted Jul 31, 2026

The WEX Fleet Services team which owns the Over the Road experiences is transforming the future of fleet payments by building agentic, scalable solutions that power WEX’s industry-leading fuel card platform. We design and develop new capabilities that enable delightful experiences for both internal and external customers, creating the foundation for new products, services, and business opportunities.

We are looking for a passionate Senior Software Development Engineer who enjoys solving complex problems, passionate about learning and experimenting, building innovative solutions, and collaborating with a talented engineering team. In this role, you will play a key part in designing, developing, and enhancing agentic solutions in a cloud-native environment using industry-leading AI tools/platforms, Java, AWS, Kafka event streaming, Elasticsearch, containerization, and API-driven architectures.

This is an opportunity to join an agile, collaborative team where engineers have ownership, make meaningful technical contributions, and deliver solutions that directly impact WEX’s customers and business growth.

How You’ll Make an Impact

  • Design, develop, and deliver delightful product experiences that are powered by Agentic capabilities, scalable, reliable software solutions using modern technologies such as Java, Kafka, Elasticsearch, and cloud-native platforms.

  • Contribute to architecture and design decisions that support highly available, secure, and scalable systems.

  • Build and maintain clean, efficient, well-tested, and maintainable code.

  • Develop and optimize RESTful APIs and backend services.

  • Participate in code reviews, technical discussions, and collaborative problem-solving sessions.

  • Troubleshoot, debug, and resolve complex technical challenges.

  • Work across technology stacks and quickly adapt to new tools and frameworks.

  • Stay current with emerging technologies and industry best practices to continuously improve engineering practices.

  • Ensure operational excellence and best customer experience for all the products and systems owned by the team.

Experience You’ll Bring

  • Bachelor’s degree in Computer Science, Engineering, or a related technical field.

  • 7+ years of software engineering experience designing, developing, and supporting enterprise-scale applications.

  • Strong experience building cloud-based applications and infrastructure using infrastructure-as-code practices.

  • Proficiency with event streaming platforms such as Kafka.

  • Experience with Elasticsearch, including indexing strategies, query optimization, and data analysis.

  • Experience working with cloud platforms such as AWS.

  • Strong understanding of software engineering principles, including data structures, algorithms, object-oriented design, scalability, availability, and reliability.

  • Strong problem-solving skills with the ability to analyze complex technical challenges.

  • Excellent written and verbal communication skills with a collaborative mindset.

Preferred Qualifications

  • Master’s degree in Computer Science, Software Engineering, or a related field.

  • 8+ years of software engineering experience.

  • Experience and knowledge in building Agentic/AI solutions for real world problems.

  • Experience designing and implementing event-driven architectures.

  • Experience working with card payments or financial services platforms.

  • Hands-on experience with cloud-native technologies including Docker and Kubernetes.

  • Knowledge of API security principles and PCI DSS compliance requirements.

  • Experience working within existing codebases and improving legacy systems.

  • Strong backend development expertise with Java or C#, including frameworks such as Spring Boot.

  • Experience designing, building, and optimizing RESTful APIs, OData services, and SQL-based solutions.

  • Proven experience developing internet-scale services with a focus on scalability, security, availability, and reliability.

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: $140,600.00 - $173,100.00

Want jobs like this matched to you?

SimpleCareer scores fresh postings against your résumé so you only see the matches that matter.

Get started free