Senior Software Engineer – Payments Modernisation - Part-Time

Role Overview

We are seeking experienced Senior Software Engineers to join a mission-critical payments modernization program. This role focuses on stabilizing, upgrading, and modernizing legacy systems rather than building new features. You will play a key role in elevating engineering standards, improving system resilience, and ensuring compliance across core financial systems. This is an opportunity to work on high-impact platforms in a lean, high-performing team, contributing as a hands-on engineer with strong ownership.

Key Responsibilities

• Lead modernization of legacy applications (Java 8 → Java 21+) to improve performance, maintainability, and compliance
• Enhance application hygiene, including testing, observability, and system reliability
• Implement and support containerized deployments using Kubernetes and cloud platforms (AWS preferred)
• Work on mission-critical payment systems, ensuring stability and operational continuity
• Collaborate closely with engineering leads in pair programming and technical design sessions
• Identify and reduce technical debt across existing systems
• Contribute as an independent engineer in a lean team with minimal supervision

Required Skills & Experience

Core Technical Skills:

• Strong expertise in Java (preferably Java 21+) or Python
• Experience working with microservices and containerization (Kubernetes)
• Hands-on experience with AWS or similar cloud platforms
• Solid understanding of software engineering best practices (testing, CI/CD, observability)

Domain Expertise:

• Experience in financial services, fintech, or payments systems
• Knowledge of payment processing (ACH, Swift, or similar) is highly desirable

Working Style:

• Proven ability to work on legacy systems with modernization goals
• Comfortable operating as a self-starter and individual contributor
• Strong problem-solving skills with a focus on system improvement rather than greenfield development

Preferred Qualifications

• Experience upgrading large-scale systems across Java versions
• Familiarity with compliance-driven environments (audit, regulatory frameworks)
• Exposure to observability tools and automated testing frameworks
• Prior experience in high-availability or mission-critical systems

What We’re Looking For

• Engineers who thrive on improving and modernizing existing systems
• Individuals who can lead through expertise and initiative, not just follow requirements
• Team players who value clear communication and strong collaboration in lean teams
• Professionals who understand the realities and challenges of legacy system transformation

We regret to inform that only shortlisted candidates will be notified.

EA Registration No: R21103843, Andrew Jonas Matthew

Allegis Group Singapore Pte Ltd, Company Reg No. 200909448N, EA Licence No. 10C4544