Payments Platform Engineer II (EMV, Tokenization)

United States Digital Space LLC; United States; Remote; USD 110,000 - 160,000; Full time

Job summary

United States Digital Space LLC, headquartered in Irvine, California, develops integrated payment solutions for ERP, CRM, Mobile and eCommerce. The team seeks a Software Engineer II to build secure payment solutions across EMV terminals, backend services, and integrations, with emphasis on EMV certification, tokenization, and end-to-end transaction flows.

The role collaborates with senior engineers to deliver reliable, compliant, and scalable payments software, including RESTful APIs,

Qualifications

• 2-4 years of professional software development experience.
• Experience working on payment systems, financial systems, or API integrations.
• Experience building RESTful APIs using .NET / ASP.NET Core.
• Experience developing Android applications using Kotlin.
• Understanding of the payment transaction lifecycle from authorization through settlement.
• Strong debugging and problem-solving skills in production environments.
• Ability to work collaboratively in cross-functional teams.

Responsibilities

• Develop and maintain Ingenico terminal applications using Kotlin and Ingenico SDK.
• Implement EMV transaction flows (contact, contactless, NFC, wallet).
• Integrate terminal software with host systems and gateway APIs.
• Troubleshoot device-level issues, EMV kernel interactions, and transaction failures.
• Assist with firmware updates and terminal configuration management.
• Contribute to secure RESTful APIs using .NET/ASP.NET Core.
• Implement core payment workflows: authorization, capture, refund, void, and settlement.
• Support integrations with payment processors and gateways.
• Build and maintain device management services (registration, monitoring, configuration).
• Implement webhook listeners and event-driven payment updates.
• Support batch settlement, reconciliation, and reporting processes.
• Participate in production troubleshooting and reliability improvements.
• Contribute to EMV Level 3 certification efforts and test case execution.
• Assist in validating host message formatting and transaction responses.
• Troubleshoot processor-level declines and edge cases with guidance from senior engineers.

Skills

RESTful APIs

Kotlin Android

Payment APIs

Debugging

Cross-functional

Job description

United States Digital Space LLC, headquartered in Irvine, California, develops integrated payment solutions for ERP, CRM, Mobile and eCommerce. The team seeks a Software Engineer II to build secure payment solutions across EMV terminals, backend services, and integrations, with emphasis on EMV certification, tokenization, and end-to-end transaction flows.

The role collaborates with senior engineers to deliver reliable, compliant, and scalable payments software, including RESTful APIs,