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.

Currently focused on

Secure Java microservices, banking-grade APIs, cloud-native backend systems, and production reliability.

Java & Spring Boot AWS & cloud-native Distributed systems

Engineering perspective How I think about backend systems

Selected work

Architecture with an operational point of view.

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

All case studies

Featured case study

Secure Banking API Integration Platform

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.

Read the case study

Technical writing by Ishan

Notes from the backend.

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

Browse all writing

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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