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