Hi, I'm Shamodha Sahan
Strategic engineer with 4+ years enterprise experience, 6+ years full-stack engineering, and 60+ delivered client releases. Specialized in high-throughput reactive APIs (Spring WebFlux), Kubernetes/K3s clustering, multi-tenant schema isolation, and deep learning computer vision.
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.build();
Production Architecture Blueprints
Real enterprise blueprints architected for mission-critical reliability, multi-tenant isolation, and sub-millisecond query performance.
High-Availability SaaS ERP on Kubernetes & OpenStack
Executive Architectural Summary
Architected for Softwater Centralized ERP. Deployed on dedicated OpenStack compute instances running high-availability Kubernetes (K8s) clusters with Nginx reverse proxy ingress controllers, Spring Boot polyglot microservices, and PostgreSQL primary-replica topologies.
Core Engineering Bottlenecks Solved
- •Unpredictable concurrent billing loads causing CPU throttling on monolithic servers
- •Zero-downtime requirement during statutory month-end billing ledger closures
- •Strict tenant data privacy across regional water utility boards
Technical Implementation & Mechanisms
- Horizontal Pod Autoscalers (HPA) responding to CPU/memory saturation metrics within 15 seconds
- Read/write split connection pooling directing heavy reporting queries to read replicas
- Automated rolling deployments via GitHub Actions and Helm charts with zero dropped packets
Deployed Stack & Infrastructure
Featured Engineering Works
Proven enterprise systems, multi-tenant SaaS backends, computer vision models, and production e-commerce platforms.
Softwater Centralized SaaS ERP
Enterprise resource planning (ERP) platform designed for large-scale water distribution, billing automation, customer account provisioning, and live monitoring across provincial utilities.
Multi-Tenant Point of Sale (POS) Engine
Centralized high-throughput POS backend powering multi-branch retail chains with dynamic tenant schema routing, automated migrations, and sub-millisecond Redis caching.
AI-Powered Blockchain Healthcare System
Novel healthcare verification framework integrating Ethereum smart contracts with deep learning computer vision to eliminate counterfeit medical prescriptions and pharmaceutical fraud.
Enterprise RAG Engine & AI Assistant
Production Retrieval-Augmented Generation system enabling enterprise teams to query multi-gigabyte technical documentation, PDFs, and internal codebases with near-zero hallucination.
InfraPulse Distributed Metric Ecosystem
Distributed infrastructure health monitoring framework featuring ultra-lightweight daemon agents, high-frequency time-series ingestion, and live React WebSocket dashboards.
IoT Telemetry & PyCycle Logistics Hub
Real-time transport fleet management system bridging embedded hardware sensors with enterprise cloud backends for automated fuel efficiency and route optimization at Ritz Garment.
Signal Forge Predictive Market Engine
High-speed cryptocurrency market analytics engine processing live WebSocket ticker feeds across tier-1 exchanges with LightGBM predictive pricing models.
TimeFlow Enterprise HR & Payroll ERP
Comprehensive enterprise workforce platform handling automated biometric attendance synchronization, statutory tax computations, and automated salary slips for OC Technologies.
HyperTech E-Commerce Platform
Production electronics retail portal supporting real-time product catalogs, shopping cart persistence, and multi-gateway payment processing via Koko Pay and Payzy.
Kurtashia Fashion Apparel E-Commerce
Apparel sector e-commerce web application featuring tokenized checkout flows, encrypted payload transmission, and Cloudflare edge domain caching.
Enterprise Experience
Track record of leading engineering pods, architecting multi-tenant cloud backends, and delivering zero-downtime releases.
- Lead and mentor an engineering team of 5+ developers, establishing Agile sprint velocity and zero milestone delays.
- Architect centralized SaaS ERP platforms utilizing React, Spring Boot, OpenStack, Docker, and Kubernetes clusters, scaling backend infrastructure to support 10,000+ concurrent enterprise users with zero downtime.
- Optimize multithreaded backend execution, thread pool allocation, and database query indexes to maximize throughput and minimize latency under peak transaction volumes.
- Direct technical architecture reviews, CI/CD automated gates, and microservices decomposition strategies.
- Lecturer & Coursework Lead for Software Architectures & Design Patterns II: Designing and delivering technical curriculum covering Monolithic vs. Polyglot Microservices, Event-Driven Architecture, SOLID Principles, and GoF Design Patterns.
- Hands-on Lead for Rapid Application Development (RAD): Mentoring and architecting full-stack production systems using modern MERN Stack (MongoDB, Express.js, React, Node.js) with clean architecture boundaries.
- Lead for Advanced Mobile Development: Instructing cross-platform mobile engineering with React Native, state management, native device APIs, and high-performance offline caching.
- Deliver practical cloud laboratories on Polyglot Microservices (Spring Boot, Spring WebFlux, Express.js, Flask), Docker containerization, Azure VM administration, Nginx load balancing, K3s Kubernetes clustering, and GitHub Actions CI/CD pipelines.
- Audit developer codebases, enforcing clean architecture patterns, data encryption standards (AES/RSA), secure GCP Secret Manager credential injection, and zero-delay execution.
- Engineered modular web components and scaled backend logic for multi-tenant enterprise applications processing high-volume daily transactions with zero downtime.
- Orchestrated Point of Sale (POS) backends implementing strict PostgreSQL schema separation per tenant, automated migrations via Flyway, and Redis caching layers, reducing data retrieval latency by up to 40%.
- Enforced PCI DSS-compliant credential management using GCP Secret Manager and dynamic environment injection, eliminating hardcoded secrets across CI/CD pipelines.
- Architected secure backend microservices for 'Olo Emergency Car Breakdown & Roadside Service System', a mission-critical car service dispatch platform.
- Implemented strict PCI DSS standards for card processing, end-to-end data encryption (AES/RSA), and cryptographic hashing (SHA-256), seamlessly integrating Stripe and PayPal payment gateways.
- Engineered 'Slidee Real-Time Chat', a mobile-responsive communication platform utilizing React, Spring Boot, and Firebase for real-time synchronization, deployed on Google Cloud Platform with IPG integrations.
- Engineered full-stack web and mobile systems leveraging modern JavaScript/TypeScript frameworks and optimized relational database queries.
- Managed production Linux server provisioning (Linode/Ubuntu), Nginx reverse proxy configurations, UFW firewall security rules, and automated deployment pipelines.
- Spearheaded development of 'TimeFlow Enterprise HR & Payroll ERP', integrating complex leave ledgers and automated salary disbursement calculation engines.
- Delivered 30+ scalable end-to-end full-stack architectures for international and local clients, managing complete SDLCs from cloud infrastructure provisioning to secure payment gateway integrations.
- Engineered live commercial solutions including HyperTech E-Commerce and Kurtashia Fashion with tokenized Koko Pay, Payzy, and custom Cloudflare DNS routing.
- Provided consultative architecture audits for startups transitioning from monolithic frameworks to containerized microservices.
Lecturing & Technical Mentorship
Educating over 500+ aspiring software engineers and developers in Enterprise Software Architecture, Rapid Application Development (MERN Stack), Advanced Mobile Development (React Native), and Cloud Microservices.
Software Architectures & Design Patterns
- ›Monolithic vs. Polyglot Microservices Architectures
- ›Event-Driven Architecture & Message Queue Topologies
- ›SOLID Principles, Clean Architecture & GoF Design Patterns
- ›Domain-Driven Design (DDD) & Bounded Contexts
Rapid Application Development (RAD) — MERN Stack
- ›Full-Stack Architectures with MongoDB, Express.js, React & Node.js
- ›RESTful API Design, JWT Authentication & Role-Based Access Control
- ›State Management, Component Lifecycle & Optimized Frontend Rendering
- ›Agile Sprint Delivery, Rapid Prototyping & Production Deployment
Advanced Mobile Development — React Native
- ›Native Device APIs, Camera, Biometrics & Hardware Sensors
- ›High-Performance Offline Data Caching & Local Database Synchronization
- ›Navigation Stacks, Fluid Gestures & Responsive Mobile UI/UX
- ›Production Mobile App Store & Google Play Packaging and Deployment
Enterprise Cloud Infrastructure & Reactive Systems
- ›Spring WebFlux Reactive APIs & Project Reactor Non-Blocking I/O
- ›Multithreading, Thread Pool Allocation & Concurrency Control
- ›Docker Containerization & Kubernetes (K3s) Micro-Clustering
- ›Azure VM Provisioning, Nginx Load Balancing & Reverse Proxies
- ›Automated CI/CD Pipelines with GitHub Actions & Code Audits
Published Packages & CLI Tools
Production libraries and tooling published on Maven Central and the NPM Registry with cryptographic GPG signing and automated CI/CD releases.
jwt-security-spring-boot-starter
Production-ready Java security starter enabling auto-configured JWT authentication, filter-chain injection, and RBAC authorization for Spring Boot 3 enterprise microservices. Published to Sonatype Central with GPG key signing.
<dependency>- •Auto-configured Spring Security 6 / Spring Boot 3 filter chains
- •Zero-boilerplate JWT creation, verification, and claims extraction
- •Role-Based Access Control (RBAC) method security annotations
- •GPG-signed binary verification and published on Maven Central
jwt-auth-express-kit
Type-safe JWT authentication and role-based access control (RBAC) middleware package for Express.js and TypeScript backends, accompanied by an interactive terminal CLI configuration wizard.
npm install jwt-auth-express-kit- •Strict TypeScript typing for authenticated Express Request objects
- •Pre-built middleware for role hierarchies and permission guards
- •Automatic token expiration refresh workflows and blacklist hooks
- •Interactive CLI wizard to scaffold authentication boilerplates in seconds
create-node-ss
Command-line interface (CLI) scaffolding tool engineered to accelerate the initialization of production-grade Node.js backends. Generates ESM modules, comprehensive TypeScript architectures, and Docker configurations.
npx create-node-ss my-backend-api- •Instant scaffolding for Clean Architecture / Controller-Service-Repository patterns
- •Native ECMAScript Modules (ESM) with zero Babel or transpilation headaches
- •Pre-configured ESLint, Prettier, Jest, Dockerfile, and GitHub Actions CI
- •Automated Git repository initialization and dependency installation
kubebot-cli
Dedicated command-line interface software package built to streamline Kubernetes cluster inspection, deployment rollouts, pod log streaming, and container management workflows.
npm install -g kubebot-cli- •Simplified shorthand aliases for complex kubectl commands
- •Interactive cluster context switching and namespace inspection
- •Live multi-pod streaming logs with regex filtering
- •Automated health checks and resource usage visual diagnostics
Comprehensive Tech Arsenal
Rigorous hands-on mastery spanning reactive Spring microservices, Kubernetes orchestration, multi-tenant databases, and deep learning vision pipelines.
Languages & Core Systems
Backend & Distributed Frameworks
Cloud, DevOps & Containers
Databases, Caching & Migrations
AI, ML, Computer Vision & IoT
Security, Cryptography & Payments
Frontend & Mobile Engineering
Education & Research Degrees
Rigorous foundations in computer science theory, algorithms, machine learning research, and enterprise software engineering.
Bachelor of Science (Hons) in Computer Science
Applied Machine Learning, Emerging Technologies, Research and Professional Issues.
Graduate Diploma in Software Engineering (GDSE)
Enterprise Java Architecture, Advanced OOP, Data Structures & Algorithms, Polyglot Microservices, Hibernate/ORM, AWS Cloud Deployment, and Machine Learning.
G.C.E. Advanced Level (A/L) – Mathematics Stream
Combined Mathematics, Physics, and Chemistry.