Senior Backend Engineer - Card-Present Payments (EMV, .NET)

EBizCharge; Irvine (CA); On-site; USD 140,000 - 200,000; Full time

Job summary

EBizCharge is expanding its Card Present platform, building backend services that power in-person payments, including tap, dip, and swipe transactions at POS. We seek a Senior Engineer who blends payments domain expertise with strong backend fundamentals.

You will design and implement scalable .NET/C# services, ensure PCI DSS compliance, and mentor junior engineers while collaborating with terminal SDKs such as Clover, Stripe Terminal, and Square.

Qualifications

• Proficiency in C# and the .NET ecosystem with production-grade backend experience.
• Hands-on experience with EMV payment flows (chip, contactless, magnetic stripe) and Level 3 certification.
• Experience integrating with payment terminal hardware and device management platforms (TLV/ISO 8583 or equivalent).
• Strong understanding of PCI DSS requirements for card-present environments including encryption and key management.
• Experience building RESTful APIs with clear versioning and high reliability.

Responsibilities

• Design, develop, and maintain backend services that manage communication between payment terminals and processing infrastructure.
• Integrate with terminal SDKs and adapt APIs to fit our platform architecture.
• Own and drive EMV Level 3 certification efforts with networks and device vendors.
• Design and build card-present infrastructure for international markets and varied certification requirements.
• Build scalable, low-latency backend services using .NET/C# and ensure robust retry logic and fault tolerance.

Skills

C#/.NET

EMV payment flows

API design

PCI DSS

RESTful APIs

Tools

Clover SDK

Stripe Terminal SDK

Square SDK

Job description

EBizCharge is expanding its Card Present platform, building backend services that power in-person payments, including tap, dip, and swipe transactions at POS. We seek a Senior Engineer who blends payments domain expertise with strong backend fundamentals.

You will design and implement scalable .NET/C# services, ensure PCI DSS compliance, and mentor junior engineers while collaborating with terminal SDKs such as Clover, Stripe Terminal, and Square.