Senior Android Payments Developer

Greetings from Ubique Systems!!!

We are looking for a Senior Android Payments Developer for one of our customer who has an expertise in:-

Key Responsibilities:

· Design and implement Android applications for point-of-sale terminals: deliver

clean, maintainable Java/Kotlin code that runs on embedded Android and

AOSP-based POS 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 and device-specific APIs

expected).

· Payment flow implementation: author authorisation, settlement, reversal and

offline-capable flows; ensure correct handling of EMV, contactless and

magnetic stripe scenarios.

· Support payment certification: prepare artefacts, run test suites and

coordinate certification activities with card schemes and acquirers (Visa,

Mastercard, American Express and others); address scheme audit findings

and remediation.

· Contribute to legacy transformation: migrate and refactor legacy payment

codebases to modern architectures (modularisation, services, secure SDKs),

preserving backward compatibility and minimising customer impact.

· Security and compliance: implement secure coding practices, support PCI

and terminal security requirements (PCI PTS, EMV kernel considerations),

and liaise with security and HSM teams on key management interfaces.

· Performance, reliability and observability: profile and optimise application

performance, improve startup times and memory usage, and add

telemetry/diagnostics to aid support and SRE teams.

· Automation and 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.

· Defect resolution and production support: drive rootcause analysis for critical

incidents, produce fixes and participate in postrelease reviews.

· Mentoring and collaboration: review peers’ code, share knowledge across the

team, and work closely with QA leads, programme managers and product

owners to align delivery priorities.

Primary Objectives:

· Deliver high-quality Android POS applications for multiple device families

(including PAX) that meet functional, security and performance targets.

· Successfully complete payment certification cycles with major card schemes

and acquirers, achieving approval with minimal rework.

· Advance the legacy transformation programme by migrating key components

to modern, maintainable implementations while minimising disruption to

services.

· Reduce production defects and incident mean time to resolution through

better testing, telemetry and automated checks.

· Ensure software fulfils compliance requirements and is supportable in live

environments.

Knowledge & Skills:

· Strong hands-on Android development experience (Java and Kotlin) on

embedded/AOSP variants used in POS devices.

· Proven experience with POS device SDKs and hardware

integration—experience with PAX devices and SDKs highly desirable.

· Deep understanding of payment terminal flows, EMV transaction lifecycle,

contactless/NFC processing and implications for application logic.

· Practical familiarity with payment scheme certification processes and

requirements for Visa, Mastercard, American Express (preparing logs, test

cases, remediation).

· Awareness of industry security standards: PCI (including PCI PTS) and EMV

kernel behaviours; understanding of secure key management concepts and

HSM interactions.

· Experience with automated testing and CI/CD for mobile/embedded

applications: unit, integration, UI automation and device farm orchestration.

· Proficient with modern development toolchains: Android Studio, Gradle, Git;

experience with Jenkins/GitLab CI/Azure DevOps or equivalent.

· Competence in debugging on physical devices, serial/USB/Bluetooth/NFC

communications, and analysing logs and traces from constrained

environments.

· Strong analytical skills, attention to detail and methodical approach to

debugging and problem resolution.

· Effective verbal and written communication; able to prepare technical

artefacts for certification, and present technical trade-offs to product and

programme stakeholders.

· Experience working in regulated/financial environments (fintech, payments)

and in large enterprise delivery contexts.

Educational &Professional Requirements:

· Bachelor’s degree in Computer Science, Engineering or equivalent practical

experience.

· Relevant certifications (Android, EMV, PCI or equivalent) are advantageous.

· Demonstrable track record of shipping payment terminal software and

participating in card-scheme certification or acquirer testing is highly desirable

Employment type:-Contract.

It would be remote working within Nenagh, Ireland only.

Note:-Only apply if you have valid visa in the EU Region, Sponsorship will not be given.