Software Engineer (Payment Systems)

Job Description:

• Location – Hybrid (2-3x days on-site): Lincolnshire, IL 60069
• Duration: 12mo(s) contract with extensions and potential to convert perm based on performance

Day-to-Day: A large retail company is seeking an experienced Software Engineer in Payment Systems with strong .NET/C# expertise. This role focuses on designing, building, and maintaining secure, high-performance payment platforms by developing reliable transaction processing systems using .NET, C#, and ASP.NET Core, building RESTful APIs and microservices, integrating with payment gateways and banks, ensuring high availability and scalability, implementing PCI DSS compliant secure handling of sensitive payment data, monitoring transaction flows, troubleshooting production issues, and improving reconciliation and settlement processes.

Required Qualifications:

• 8+ years of hands-on experience with C#, .NET, and ASP.NET Core
• 5+ years of experience in retail and multi-channel payments (POS, e-commerce, mobile, and alternative payment methods)
• Strong experience building RESTful APIs, microservices, and backend distributed systems
• Proficiency with relational databases (SQL Server, Oracle, or PostgreSQL)

Preferred Qualifications:

• Experience integrating with payment processors and gateways (Stripe, Adyen, PayPal, Fiserv, Authorize.net, etc.)
• Familiarity with cloud platforms (Azure or AWS) and cloud-native .NET applications
• Familiarity with SOX or other financial compliance standard