About Me.
I am Software Engineer specializing in backend development with Java, Spring Boot, and SQL databases.
With practical experience designing APIs, integrating complex third-party platforms, and optimizing transaction flows within the fintech sector, I focus on writing clean, robust, and performant code.
I leverage AI-augmented development to bridge the gap between complex research and production-grade software. I thrive in Agile environments, transforming intricate technical requirements into clean, scalable code that drives real-world value.
Download CVTechnical Skills.
Languages
Frameworks & Tech
Databases
Tools & Architecture
Professional Experience.
Associate Software Engineer
iPay Sri Lanka | iPay Cambodia
Fintech & Payment Infrastructure
- Designed and developed a cross-border remittance architecture for LOLC Cambodia, implementing dual-currency (KHR/USD) QR generation and payment processing mechanisms.
- Integrated the National Bank of Cambodia (NBC) SDK to dynamically generate standard-compliant KHQR codes, streamlining inter-bank mobile transactions.
- Architected a real-time, rule-based Fraud Risk Management (FRM) system for mobile banking, mitigating transaction risks through immediate pattern analysis.
- Orchestrated a critical system migration for iPay Sri Lanka, transitioning core API integrations from legacy SOAP protocols to high-performance REST services via the mCash switch.
- Implemented seamless deep-link integrations for the Phnom Penh Water Supply Authority (PPWSA) within the iPay ecosystem, optimizing the customer journey for digital utility payments.
- Designed, documented (via Swagger), and optimized scalable backend REST APIs supporting complex fintech features.
Core Banking & Loan Services
- Engineered and launched digital lending microservices, including Salary Advance Loans and Gold Financing solutions for LOLC Cambodia.
- Overhauled and optimized the main payroll module to reliably execute 10,000+ monthly transaction cycles using transactional retries and robust recovery fallbacks.
- Led backend developments for the new customer digital onboarding journey on the LOLC Mobile Cambodia application, accelerating user acquisition.
- Integrated secure, high-availability third-party components, including SMS gateways, payment gateways, and Card Management Services (CMS).
Architecture, Security & Governance
- Enforced strict code quality benchmarks across core codebases by identifying and resolving structural vulnerabilities and code smells using SonarQube.
- Spearheaded application security enhancements, implementing hardening practices to protect sensitive customer data and transactional endpoints.
- Troubleshot real-time production issues, securing system uptime, performance integrity, and datastore optimizations.
- Conducted R&D on modern microservices architectures and established detailed design guidelines for engineering teams.
Software Engineering Intern
iPay Sri Lanka | iPay Cambodia
- Participated in Agile sprint planning, standups, and retrospective activities to ensure timeline alignment.
- Contributed to software quality assurance by designing, tracking, and executing integration and system test plans.
- Identified critical system bugs, fixed backend anomalies, and resolved SQL querying bottlenecks.
- Wrote unit and integration test suites using JUnit to raise application test coverage and system confidence.
- Assisted in Java-based feature development, query tuning, and live production release support.
Freelance Software Developer
Self-Employed
- Engineered custom Web and Backend applications utilizing Spring Boot, Thymeleaf, and MySQL for local small businesses.
- Designed external API integrations to connect e-commerce services with billing and notifications.
- Created responsive user interfaces and customized digital graphics to elevate branding.
- Provided technical consultation, automation setups, and ongoing application updates for clients.
Selected Projects.
Call Management System
A web dashboard visualizing performance stats, duration analytics, and connection states for an AI-powered conversational calling agent.
View SourceAdSync
An intelligent advertising display system utilizing image recognition to detect human age and target demographic-specific marketing content in real time.
View SourceProject Tools
A personal suite of productivity interfaces built rapidly using prompt engineering and generative workflows, deployed for daily tasks.
View SourcePassenger Forecasting
A data forecasting study analyzing monthly air passenger counts in Sri Lanka, published on Kaggle. Compares ARIMA and Prophet models for tracking trends.
View Dataset & ModelsAchievements & Athletics.
Certifications & Awards
- National Olympic Committee of Sri Lanka: Sports Administrators Course (SAC) Certificate.
- University of Moratuwa: Sri Lanka Robotics Challenge 2017 – Runner-Up (School Category).
- SLIIT ICT Quiz Contest 2018: Merit Award.
- The Institute of Western Music & Speech (2010): All-Island Graded Examination Prize Winner.
Sports & Athletics
- Indoor Archery Youth Cup 2013 (Singapore): Gold Medalist (B Division) • 2nd Place Overall (International).
- Colombo Archery Classic (2021): Stage 3 Open Men – 2nd Place.
- Wayamba All-Island Archery Championship (2017): Under 17 Boys – 2nd Place.
- 5th Junior National Archery Championship (2015): 1st Place (Under 18 Mixed Team, Under 14 Boys Team) • 2nd Place (Under 20 Boys) • 3rd Place (Under 17 Boys).
- 4th Junior National Archery Championship (2014): 1st Place (Under 18 Mixed Team, Under 14 Boys Team) • 2nd Place (Under 20 Boys) • 3rd Place (Under 17 Boys).
- 3rd Junior National Archery Championship (2013): 1st Place (Under 16 Boys, Under 18 Mixed Team, Under 14 Boys Team) • 2nd Place (Under 14 Boys).
- School Provincial Games (2018): Badminton Under 20 (Team) – 2nd Place • Table Tennis Under 20 (Team) – 2nd Place.
- School Provincial Games (2017): Table Tennis Under 20 (Team) – 1st Place • Badminton Under 20 (Team) – 2nd Place.
- School Provincial Games (2016): Badminton Under 19 (Team) – 2nd Place • Table Tennis Under 19 (Team) – 3rd Place.
- School Provincial Games (2014): Badminton Under 15 (Team) – 3rd Place.
- School Provincial Games (2013): Badminton Under 15 (Team) – 3rd Place.
- Bandarawela Tennis Club 115th Annual Club Tournament (2012): Boys Under 14 Doubles Event – 2nd Place.
Recommendations.
"Thanuja was a hardworking and committed student who showed a genuine interest in database systems and machine learning. During his Final Year Project, he demonstrated outstanding dedication, responsibility, and a positive attitude toward feedback. His consistent effort and willingness to learn make him a strong candidate for any software engineering role."
Nethmi Wijesinghe
PhD Candidate at RMIT • Casual Academic • Researcher
"I worked with Thanuja during my tenure as a Delivery Manager at iPay. On the Cambodia project, he consistently demonstrated strong technical capability, diligence, and a dependable work ethic. He is a highly reliable professional who approaches his tasks with clear ownership and collaborates exceptionally well."
Sanka Abeysirigunawardena
Senior Business & Test Analyst • Delivery Manager • FinTech Specialist
"Thanuja demonstrated strong technical skills and a genuine passion for problem-solving from day one. What stood out most was his willingness to go the extra mile—diving deep into complex tasks and taking initiative to improve core processes. He is a dedicated, highly collaborative team player who delivers quality code under tight deadlines."
Rukshan Sooriyaarachchi
Business Consultant • Product & Service Delivery Expert
Get In Touch.
Let's discuss backend architecture, fintech systems, integration setups, or sports. Drop a message!