Senior Payments Backend Engineer — Scale Secure APIs

Gables Search Group; Chicago (IL); On-site; USD 110,000 - 160,000; Full time

Job summary

Gables Search Group is seeking an experienced Software Engineer - Payments to develop secure, scalable payment services for a large, multichannel business. This hands-on backend role will work with C# and .NET while integrating processors, gateways, and third‑party platforms to support transactions across in-store POS, e‑commerce, mobile, kiosk, and call center environments.

Local candidates only in Chicago, IL; no visa sponsorship is available.

Qualifications

• 5–10 years of professional software engineering experience.
• Hands-on development with C# and .NET/.NET Core.
• Experience building REST APIs and integrating third-party platforms.
• Background with relational databases (SQL Server / PostgreSQL).
• Experience troubleshooting production or transaction-processing systems.
• Knowledge of secure development practices and data protection.

Responsibilities

• Build and enhance payment services and REST APIs using C# and .NET/.NET Core.
• Develop integrations with processors, gateways, acquiring banks, digital wallets, and external providers.
• Support authorization, capture, settlement, refunds, chargebacks, and transaction routing.
• Improve retry logic, exception handling, failover, observability, and transaction success rates.
• Troubleshoot production issues across applications, APIs, and third-party systems.
• Participate in solution design, code reviews, incident response, and root-cause analysis.
• Partner with Product, Architecture, and engineering teams to deliver reliable payment capabilities.
• Write secure, maintainable, well-tested code for business-critical systems.

Skills

C#

.NET

REST APIs

SQL Server

PostgreSQL

Payments experience

Troubleshooting

Tools

Kafka

RabbitMQ

Azure Service Bus

Job description

Gables Search Group is seeking an experienced Software Engineer - Payments to develop secure, scalable payment services for a large, multichannel business. This hands-on backend role will work with C# and .NET while integrating processors, gateways, and third‑party platforms to support transactions across in-store POS, e‑commerce, mobile, kiosk, and call center environments.

Local candidates only in Chicago, IL; no visa sponsorship is available.