Senior Android Engineer (POS)

The Senior Android Developer (POS) is responsible for designing, developing, and optimizing Android - based Point of Sale (POS) applications, with a strong focus on payment integrations and hardware interaction. The role requires deep expertise in POS ecosystems (Sunmi & PAX), secure payment technologies, and smart card integrations . 1. POS Application Development Design, develop, and maintain Android POS applications for Sunmi and PAX devices. Handle device - specific integrations including printers, card readers, scanners, and peripherals. Optimize application performance for embedded POS environments with limited resources. Ensure compatibility across different POS SDKs and hardware architectures . 2. Payment & Transaction Processing Implement and manage payment flows using EMV (contact & contactless) standards. Integrate transaction messaging using ISO - 8583 protocols. Ensure secure handling of financial transactions in compliance with industry standards. Troubleshoot and resolve transaction - related issues in production environments. 3. Smart Card & NFC Integration Develop and maintain integrations with prepaid utility cards. Work with: NFC / APDU communication. IFARE, DESFire, and CPU cards Ensure secure card communication and data handling. Optimize card reading performance and reliability. 4. Architecture & Code Quality Design scalable and maintainable Android architectures using Java & Kotlin. Enforce coding standards, best practices, and secure development principles. Conduct code reviews and ensure high - quality deliverables. Lead technical design discussions and solution architecture. 5. Cross - Platform & SDK Adaptation Navigate and adapt to differences between Sunmi and PAX SDKs, including: Printing frameworks Card reader APIs Peripheral handling Build reusable components to standardize development across devices 6. Collaboration & Stakeholder Management Work closely with product, QA, and backend teams to deliver end - to - end solutions. Collaborate with external vendors and payment providers when needed. Provide technical guidance and mentorship to junior developers. Requirements Bachelor’s degree in Computer Science, Software Engineering, or a related field. 3 - 5 years of Experience in a similar role. Proven hands-on experience with POS systems (Sunmi & PAX) Experience in payment integrations and fintech environments is highly preferred. Strong proficiency in Java with solid experience in Kotlin Hands-on experience with: -EMV (contact & contactless) -ISO-8583 messaging -NFC / APDU communication -MIFARE, DESFire, CPU cards Strong understanding of Android SDK, architecture patterns, and performance optimization Experience working with hardware-integrated applications