Senior POS Developer New

Location: Nenagh, Co. Tipperary, Ireland (Onsite)

Overview:

Expleo is seeking a Senior Android Payments Developer to lead the development of card acceptance applications on POS devices and play a pivotal role in a legacy modernisation programme. You will design and implement secure, high-performance Android software for payment terminals (including PAX devices), collaborate with QA, product, and programme teams, and drive payment certification with major card schemes.

Key Responsibilities:

• Design and implement Android applications for POS terminals, delivering clean, maintainable Java/Kotlin code for embedded Android/AOSP-based devices.
• Integrate with POS hardware, implementing and validating drivers and SDK integrations for card readers, PIN pads, NFC/contactless, EMV readers, printers, and other peripherals (experience with PAX SDKs preferred).
• Implement payment flows including authorisation, settlement, reversal, and offline-capable scenarios; ensure correct handling of EMV, contactless, and magnetic stripe transactions.

• Prepare artefacts, execute test suites, and coordinate payment certification activities with card schemes and acquirers (Visa, Mastercard, Amex).
• Address scheme audit findings and remediation promptly.
• Apply secure coding practices and support PCI and terminal security requirements (PCI PTS, EMV kernel considerations).
• Collaborate with security and HSM teams on key management interfaces.

• Migrate and refactor legacy payment codebases to modern architectures (modularisation, services, secure SDKs), preserving backward compatibility and minimising customer impact.

• Profile and optimise application performance, improving startup times and memory usage.
• Implement telemetry and diagnostics to aid support and SRE teams.

• Build and maintain automated build, test, and release pipelines for terminal images and application packages.
• Support automated regression testing and device farm test runs.

• Review peers’ code, share knowledge across the team, and work closely with QA leads, programme managers, and product owners to align delivery priorities.
• Participate in post-release reviews and drive root-cause analysis for critical incidents.

Qualifications:

• Bachelor’s degree in Computer Science, Software Engineering, or a related field.
• Strong experience in Android POS development and payment integrations.
• Familiarity with PAX devices and SDKs, EMV standards, NFC/contactless payments, and PCI compliance.
• Experience with legacy system modernisation and modular application design.
• Solid understanding of CI/CD pipelines and automated testing frameworks.
• Excellent collaboration, mentoring, and communication skills.