Senior POS Developer contract

Job Title: Senior POS Developer - Nenagh Based 

Overview:
Our client is seeking a Senior Android Payments Developer to lead the development of card acceptance applications on POS devices and play a key 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.

This role is fully onsite in Nenagh, Co. Tipperary.

Responsibilities:

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

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

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

• Performance & Observability
  • Profile and optimise application performance, improve startup times and memory usage.
  • Add telemetry and diagnostics to aid support and SRE teams.

• Automation & CI/CD
  • Build and maintain automated build, test and release pipelines for terminal images and application packages.
  • Support automated regression and device farm test runs.

• Collaboration & Mentoring
  • 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.