Kotlin Backend Jobs (NOW HIRING)

We are seeking a Software Engineer II to join our growing team. This role is focused on building and supporting secure payment solutions across EMV terminals, backend services, and integrations. The ideal candidate has experience working on payment systems or processor integrations and is interested in deepening their expertise in EMV certification, tokenization, and end-to-end transaction flows. This engineer will collaborate closely with senior team members to deliver reliable, compliant, and scalable payment solutions.

EMV Terminal & Device Development

• 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

Backend Payment Services (.NET)

• Contribute to the development of secure RESTful APIs using .NET/ASPE.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

EMV Certification & Processor Integration

• Contribute to EMV Level 3 certification efforts by executing test cases and validating transaction flows
• Assist in validating host message formatting and transaction responses
• Troubleshoot processor-level declines and edge cases with guidance from senior engineers
• Support regression testing and re-certification activities
• Collaborate with internal teams and external processors during certification cycles

Tokenization & Wallet Integration

• Support implementation of network tokenization flows (Visa, Mastercard, Amex)
• Assist with token lifecycle management (provisioning, updates, de-tokenization)
• Support integrations for Apple Pay and Google Pay
• Ensure payment flows adhere to card network and security requirements

Mobile Payment Integration

• Support Android-based mobile payment integrations using Kotlin
• Integrate payment SDKs and troubleshoot mobile transaction issues
• Assist with mobile wallet provisioning and transaction flows

• 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 (authorization through settlement)
• Strong debugging and problem-solving skills in production environments
• Ability to work collaboratively in cross-functional teams

Preferred Qualifications

• Exposure to EMV Level 3 certification processes
• Experience integrating with payment processors or gateways
• Experience with Ingenico devices and SDKs
• Familiarity with PCI-DSS compliance concepts
• Experience with AWS or Azure
• Experience with CI/CD pipelines and automated deployments
• Prior fintech or payment industry experience

• Terminal Software: Ingenico SDK, Kotlin
• Backend: .NET 6+ / ASP.NET Core
• Mobile: Android SDK integration (Kotlin)
• Cloud: AWS or Azure
• Payments: EMV, Tokenization, Webhooks, Batch Settlement

This role provides hands-on experience with EMV Level 3 certification, processor integrations, and tokenized payment systems, offering a strong growth path toward senior payments engineering roles.

Job Type: Full-time

The Company is committed to compliance with all applicable laws providing equal employment opportunities. This commitment applies to all persons involved in Company operations. The Company prohibits unlawful discrimination against any job applicant, employee, or unpaid intern by any employee of the Company, including supervisors and coworkers. Pay discrimination between employees of the opposite sex or between employees of another race or ethnicity performing substantially similar work, as defined by the California Fair Pay Act and federal law, is prohibited.

Headquartered in Irvine, California, EBizCharge specializes in developing integrated payment solutions that facilitate electronic payment processing within ERP, CRM, Mobile, and eCommerce applications. Our applications are PCI compliant and fully integrated with major ERP/accounting systems, including QuickBooks, Sage, SAP Business One, Microsoft Dynamics, NetSuite, Epicor, Acumatica, and major online shopping carts, including Magento and WooCommerce. EBizCharge offers its employees tremendous learning opportunities, career growth potential, and a dynamic work environment.