Singapore · Remote / APAC friendly

Backend systems built for real-world pressure.

I’m Ishan Tharusha Wijayabahu, a senior backend engineer designing secure, high-availability Java systems for public-sector, enterprise, and cloud-native platforms.

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Java & Spring Boot AWS & cloud-native Distributed systems
system-map.yml healthy
edgeAPI Gateway
serviceOrders
serviceInventory
cacheRedis
streamEvents

Selected work

Architecture with an operational point of view.

A closer look at the decisions, trade-offs, and measurable outcomes behind production backend systems.

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Featured case study

A confidentiality-safe reference architecture for high-throughput banking APIs with Apache Camel routing, OAuth 2.0 security, transactional data, automated delivery, and production observability.

Java 17Spring BootApache CamelOAuth 2.0Oracle
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Recent writing

Notes from the backend.

Practical thinking on Java, distributed systems, performance, and cloud architecture.

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Agentic AI / Microservices

Building Smarter Microservices with OpenAI Agent Builder: Memory, Security, and Real-World Use

A practical look at adding agentic capabilities to microservices while keeping memory, security boundaries, and production concerns explicit.

 Spring Boot / Security

Securing React and Spring Boot Microservices with Hybrid Encryption (AES + RSA)

An implementation-focused guide to combining symmetric and asymmetric encryption across a React and Spring Boot application boundary.

 Java 25 / JVM

Java 25 Preview: What’s Coming in the Next Big Java Release

A code-led overview of the language and platform capabilities arriving with Java 25 and what they mean for modern backend development.

Core toolkit

Tools chosen for the problem, not the diagram.

A production-focused stack spanning application code, infrastructure, data, delivery, and observability.

JavaSpring BootMicroservicesREST APIsApache CamelAWSDockerKubernetesRedisSQLCI/CDSecurityPerformanceObservability

Have a complex backend problem?

Let’s make the system simpler, safer, and easier to operate.

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