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
- Facilitated Agile Sprint Retrospective meetings, fostering a culture of continuous improvement by identifying process bottlenecks, driving team collaboration, and implementing actionable team improvements.
- 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.
Beyond the Code.
The Garage
Vintage Restoration
Currently restoring a classic Honda CG 125, bringing an old-school machine back to its peak performance.
Sneakerhead
Deeply into sneaker culture, collecting, and tracking iconic silhouette designs.
The Trails
The Pekoe Trail
Successfully hiked Stages 1, 11, and 12 of Sri Lanka's ultimate walking trail.
Knuckles Backcountry
Trekked deep into the Knuckles Mountain Range to conquer the Duweli Ella, Sansun Ella, and the famous infinity pool.
Uva Explorer
Backpacked and covered almost every major mountain range across the Uva Province.
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!