About

About

Hi, I’m Rahul Chandna

Design, Develop, Write Tests, Refactor, Repeat.

I’m a Software Architect based in Johannesburg, South Africa. I work end to end — from Solution Design Forum through change analysis, design, development, and DevOps (understand it, build it, run it) — with deep experience in payments, multicurrency systems, and regulatory compliance for financial services.

I have in-depth experience in technical analysis, refactoring legacy code, test-driven development, and making architectural changes using infrastructure as code to meet target architecture goals.

I love sharing what I’ve learned — I’ve run numerous internal training and knowledge-sharing sessions, built a structured training programme for engineering grads, and share what I’ve picked up over the years on this blog and my YouTube channel.

Experience

Software Architect — Exaze (Mar 2023 – Present) Johannesburg, South Africa

Senior Technical Specialist — Zensar Technologies (Jan 2022 – Feb 2023) Technical leadership across a major bank’s CRM estate: built a database automation tool that cut DBA workload by ~40% with full audit trails; introduced Prometheus/Grafana observability; migrated monoliths to Kubernetes with GitLab CI/CD, cutting release times by ~30%.

Technical Specialist — Zensar Technologies (Apr 2017 – Dec 2021) Delivered regulatory programmes on the bank’s CRM platform — FATCA/CRS (AEOI) rules engine, GDPR data disposal via HSM-backed crypto-shredding — and led legacy modernisation (SOAP → Spring Boot, JPA/HikariCP, TDD refactoring across 14 services packaged into an EAR).

Senior Software Engineer — Zensar Technologies (Jul 2014 – Mar 2017) BAZEL III middleware connecting BI databases to the CRM; Anti-Money Laundering rules engine with MQ consumers; Know Your Client document capture logic. Then: JBoss → WildFly upgrade using Chef and Jenkins, Kubernetes migration from VMs, and a full modernisation of a legacy Paracon framework application (JPA, HikariCP, JWT, H2, TDD).

Software Engineer — Zensar Technologies (Sep 2011 – Jun 2014) Online Banking Enablement — integrating the CRM with OLB to automate KYC/FICA-triggered access changes. REST service extraction from a legacy monolith frontend, with JWT authentication across all APIs.

Junior Software Engineer → Trainee — Zensar Technologies (Jul 2010 – Aug 2011) Where it all started. Java, Servlets, SQL/PLSQL, Ant, Spring, paired with senior developers on production issues, and spent a lot of time in walk-through sessions with the South Africa business team to understand what was actually being built and why.

Tech

The stack that’s featured most across the years: Java (SE and EE), Spring Boot, Jersey, JAX-RS, JPA/Hibernate, HikariCP, Maven, Ant, JUnit, H2, Oracle SQL, JWT, SOAP/WSDL, Docker, Kubernetes, Helm, GitLab CI/CD, Jenkins, Prometheus, Grafana, WildFly, JBoss, Chef, NGINX, Apache, HSM integration.

This site

The posts here cover Java, Linux, Oracle, DevOps, security, and whatever else I was figuring out at the time. The earliest ones go back to 2010 — consider them reconstructed field notes.

Topics covered: Kubernetes and Docker in production, Jenkins and GitLab CI/CD pipelines, JWT and Kerberos authentication, NGINX and Apache as reverse proxies, Oracle SQL for financial data, Java JVM internals and JIT compilation, load testing with JMeter, Maven settings and profiles, multicurrency payments architecture, upgrading Java 6 to JDK 11, and Jersey + Swagger API design. More as I go.

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