Jayanga Chandrakumara

Career

Experience

1. Senior Software Engineer · Inland Revenue Authority of Singapore (IRAS)

   Oct 2023 – Oct 2026

   Contract via Avanade (Apar Pte Ltd) · Singapore

   National Tax Systems Modernisation Programme, including the myTax Portal taxpayers use to manage their income tax. Individual Tax and Enforcement domains.

   • Delivered high-traffic external REST APIs and .NET 7/8 microservices on AKS behind Azure API Management with JWT authentication, plus Angular front-end features.
   • Built Kafka event-driven services using event sourcing, and batch pipelines processing millions of records per run with safe recovery and reprocessing.
   • Improved performance through SQL Server and EF Core optimisation and Redis caching; removed race conditions with idempotent consumers and optimistic concurrency.
   • Owned production stability for the Enforcement domain, using Azure Application Insights for log analysis, distributed tracing and performance monitoring, and led incidents from root-cause analysis to permanent fixes and post-incident reviews.
   • Owned SIT, UAT and ORT exit; automated builds, xUnit tests, SonarQube quality and security scans and deployments on Azure Pipelines, with Azure Key Vault for secrets and secure-coding practices for a regulated environment.
   • Mentored junior developers and led API design, Clean Architecture, code reviews and technical documentation (Swagger specs, solution designs, operational guides).
   • Refined and estimated stories, identified technical risks and supported Agile Scrum delivery across distributed teams.

   .NET 8KafkaAzure AKSSQL ServerRedisAngular

2. Senior Software Engineer · United Overseas Bank (UOB)

   Jun 2022 – Sep 2023

   Contract via Solderfield Pte Ltd · Singapore

   UT Product Master: enterprise application Product Managers and Operations use to create and maintain Unit Trust (investment fund) products, covering fund houses, fee matrices, transaction limits and interfaces to downstream banking systems.

   • Developed Iteration 3 (Singapore) as an embedded engineer with Product Managers and Operations, using C#, ASP.NET MVC, SQL Server, EF and Elsa Workflow.
   • Led SIT and UAT releases for Iteration 3 and supported Iteration 4 UAT: deployments, environment readiness, root-cause investigation, unit-tested fixes and production deployment support.
   • Built workflow processes and data-access components integrating Unit Trust product data with downstream banking systems.
   • Managed Jenkins builds and deployments, and delivered enhancements for Iteration 4 of the SPV project.

   C#ASP.NET MVCSQL ServerEntity FrameworkElsa WorkflowJenkins
3. Senior Software Engineer · Azend Technologies Colombo, Sri Lanka (Hybrid) · Client: Huntington Learning Center (US) Dec 2021 – Jun 2022

   • Provided production support for an ASP.NET MVC application, resolving root causes across C#, EF and SQL Server.
   • Prepared and deployed production releases, validating fixes with support and business teams.

   C#ASP.NET MVCSQL Server

4. Lead Full Stack Software Engineer · QualitApps Asia (Pvt) Ltd

   Apr 2019 – Dec 2021

   Colombo, Sri Lanka · Clients in Spain

   • Led full stack delivery of the KeySave locker management platform: .NET Core Web API, mobile app integration and Angular back office.
   • Built .NET Core and Angular applications for healthcare, HR and hospitality clients, including Colegios Dental Council, Novalab Dental Clinic, Tebex and Motelink.
   • Led code reviews, set coding standards, resolved backend performance bottlenecks and established CI/CD pipelines.
   • Worked directly with Spanish client stakeholders on requirements, technical solutions and delivery.

   .NET CoreAngularTypeScriptEF CoreSQL ServerCI/CD
5. Software Engineer · CICRA Solutions (Pvt) Ltd Colombo, Sri Lanka · Clients in Australia, France, UK, Ireland Dec 2017 – Mar 2019

   • Built backend services and real-time market data feeds for TAB horse, greyhound and harness racing betting platforms.
   • Implemented PMU feed integrations and virtual racing data services delivering odds to the core e-betting platform.
   • Gathered client requirements and contributed to system design, code reviews and Agile delivery.

   C#Real-time feedsBackend
6. Junior IT Consultant · John Keells Holdings PLC Colombo, Sri Lanka · Cinnamon Hotels & Resorts Jul 2016 – Dec 2017

   • Developed an SMS marketing platform integrated with SAP ERP to promote last-minute room availability and drive direct bookings.
   • Built enterprise web applications with C#, ASP.NET, SQL Server and EF, working with business users from requirements through deployment.

   C#ASP.NETSQL ServerSAP

Toolbox

Skills

Core stack

• C#
• .NET 8
• ASP.NET Core Web API
• Microservices
• Apache Kafka
• Azure AKS
• SQL Server
• EF Core
• Redis
• Angular
• Docker & Kubernetes
• Clean Architecture & DDD

Full toolbox

Backend

C# · .NET 7/8 · ASP.NET Core Web API · Entity Framework Core · LINQ · SignalR · Elsa Workflow · JWT · REST

Messaging

Apache Kafka (Confluent) · Event-Driven Architecture · Pub/Sub

Cloud & DevOps

Azure AKS · API Management · Key Vault · Blob Storage · Application Insights · Azure Pipelines · Docker · Kubernetes · Jenkins · SonarQube

Data

SQL Server · Stored Procedures · Query tuning · Redis · MySQL

Frontend

Angular · TypeScript · JavaScript

Architecture

Microservices · Domain-Driven Design · Clean Architecture · Event Sourcing · Design Patterns

Leadership

Technical leadership · Code reviews · Mentoring · Stakeholder management · Release management

Delivery & Tools

xUnit · SIT/UAT/ORT · Agile/Scrum · Git · JIRA · Azure DevOps · GitHub Copilot · Claude

Background

Education