Backend Software Engineer Intern - C#/Java & AI Workflows (Undergraduate)

WEX is a global commerce platform that has been simplifying the way businesses operate for over 40 years. Our purpose is simple: to reduce administrative burdens, streamline payments, and manage mobility. With a team of over 7,200 professionals across 16 countries.

Our specialties are employee benefits, business payments, and fleet/mobility solutions. We support more than 20 million SaaS accounts, 8 million Health Savings Accounts, and 19+ million vehicles worldwide. We’re a growing company with a history of innovation and a focus on our customers, making this a great place to grow your career.

The WEX Summer Internship Program: Learn, Lead, and Make an Impact

Our 13-week paid internship program, running from late May to mid-August, is a chance for you to gain real-world experience and develop your skills. Recruiting begins in September and continues through November at our various locations across the U.S.

You won’t just be a bystander; you’ll work on impactful projects and contribute to WEX’s mission. We provide mentorship, professional development, and weekly learning experiences to help you build confidence and leadership skills. High-performing interns may even get the chance to lead their own initiatives.

We offer remote, hybrid, and onsite options for flexibility, and our goal is to bring top interns back full-time or offer them extended roles during the school year.

Imagine starting your career with a company that’s building what’s next. Your future starts here.

About the Team/Role:As a Software Engineer Intern, you will work alongside engineers and Product Managers to build resilient backend systems and AI-integrated workflows. You will gain hands-on experience designing scalable APIs, working in cloud environments, and leveraging modern AI toolchains.

How you’ll make an impact:

• Develop Backend Services:Design and implement RESTful APIs, microservices, and backend processing pipelines using C# or Java.
• Database & Cloud Integration: Write efficient SQL queries for SQL Server and support deployments on Microsoft Azure.
• AI-Integrated SDLC:Leverage modern AI tools (Cursor, Copilot, MCPs, AI APIs) for spec-driven development, rapid prototyping, and automated task execution.
• Learn & Collaborate:Partner with senior engineers to apply best practices in microservices and message-driven architectures (e.g., Kafka).

Experience you’ll bring:

• Educational Foundation: Currently pursuing a Bachelor’s degree in Computer Science, Machine Learning, Software Engineering, or related field and will have completed at least your Sophomore year of school at the start of the internship.
• Proficiency in C# (preferred) or Java, along with strong standard database skills (SQL / SQL Server).
• Solid understanding of API design principles, backend processing architectures, and Microsoft Azure.
• Practical experience using AI coding assistants or APIs (e.g., Cursor, Copilot, MCPs) to accelerate development.
• Knowledge of event streaming technologies (e.g., Kafka) or messaging architectures is a plus.

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: $27.00 - $35.00