Open to opportunities

Nileshka Fernando

@nileshkafernando

Software Engineer building production FinTech systems—payment gateways, trading platforms, and mobile wallet backends with Java and Spring Boot.

Sri Lanka

Message

What I'm looking for

I’m looking for a backend-focused role building reliable production FinTech systems—payment gateways and wallet/payment flows—where I can deliver secure REST APIs, maintain clean code, and collaborate on Docker-based deployments and CI/CD.

I’m a Software Engineer with experience building production fintech systems, including payment gateways, financial trading platforms, and mobile wallet applications. I focus on reliable backend solutions using Java and Spring Boot, with REST API design, security best practices, and Docker-based deployments, and I’m committed to writing clean, maintainable code.

In my Associate Software Engineer role at Arimac Lanka, I built and tested core mobile wallet transaction flows with structured error handling and observability logging, and I bridged Spring Boot with a national eKYC verification system using asynchronous flows. I also migrated Keycloak IAM from Oracle to PostgreSQL to resolve RBAC/authentication issues, optimized PostgreSQL queries for better performance, and partnered with DevOps on Docker Compose and CI/CD maintenance in Jenkins and GitLab.

Experience

Work history, roles, and key accomplishments

Associate Software Engineer

Arimac Lanka (Pvt) Ltd

Feb 2025 - Aug 2025 (6 months)

Built and tested fintech transaction flows for mobile wallets (top-up, transfers, bill payments) with structured error handling and observability logging. Designed integration services for eKYC and SOAP bill payments, migrated Keycloak IAM, and optimized PostgreSQL performance; also handled payment gateway issues including tokenisation conflicts and settlement/commission logic.

Java Spring Boot REST APIs SOAP (JAX WS)Postman SQL PostgreSQL MySQL Maven Keycloak JWT RBAC 3DS Authentication Docker Compose Linux Jenkins Gitlab CI CD Observability

Software Engineering Intern

Arimac Lanka (Pvt) Ltd

Jul 2024 - Jan 2025 (6 months)

Re-engineered a recurring payments system handling trial periods and month-end billing edge cases, and integrated an MPGS payment gateway with a Spring Boot-based financial trading platform. Implemented and tested payment REST APIs and recurring payment lifecycle flows, improving 3DS authentication and callback validation.