Sony Kalladamannil Koshy

Senior Java / Backend Engineer

Building production-grade Java microservices for cloud-native product teams.

Mississauga, ON, Canada · Open to Canada & U.S. opportunities · Canadian Citizen | TN Visa Eligible

Snapshot

11+ years delivering backend systems across retail, travel, airline, and healthcare domains.

Recent hands-on work with Java 21, Spring Boot 3, Redis, PostgreSQL, Google Pub/Sub, and GCP.

Owns services from design through production rollout, observability, support, and mentoring.

Java 21Cloud RunFirestore

Availability

Open for freelance backend engineering engagements.

About

Engineering with clarity and ownership.

I help teams ship reliable backend platforms by combining thoughtful system design with hands-on delivery. My focus is on services that stay fast, observable, and maintainable at scale: consistent REST APIs, clear domain boundaries, production-grade data flows, and integrations that can be operated with confidence.

From enterprise retail platforms to personal Cloud Run products like TriedTables, I work across backend design, third-party APIs, OAuth security, Firestore persistence, deployment automation, metrics, dashboards, and production support.

Skills

Tooling that keeps systems steady.

Java 21 / Spring Boot 3
REST APIs & Microservices
Redis / PostgreSQL / Firestore
Google Pub/Sub & Event Flows
GCP Cloud Run / Docker
OAuth2 / Admin Security
Prometheus / Grafana
OpenAI / Deepgram / ElevenLabs

Experience

Built with enterprise scale in mind.

Home Depot Canada

Senior Java / Backend Engineer

Aug 2022 - Present
  • Built Java 21 and Spring Boot 3 microservices for sponsored products, personalization, and Pro customer pricing workflows.
  • Integrated Kevel, Redis, PostgreSQL, Google Pub/Sub, and Salesforce APIs across customer-facing and associate-facing flows.
  • Added Prometheus metrics and Grafana dashboards for latency, Redis behavior, third-party health, and business event visibility.

Tata Consultancy Services (TCS)

IT Analyst / Java Developer

Jan 2017 - Apr 2021
  • Built the Singapore Airlines seat map microservice integrating with Amadeus for seat availability and selection flows.
  • Developed Spring Boot REST APIs and third-party integrations for travel, payment, booking, seat, and baggage workflows.
  • Supported IHG production systems with incident analysis, defect fixes, SLA-driven resolution, documentation, and mentoring.

Speridian Technologies

Associate Systems Engineer

Jan 2014 - Jan 2017
  • Developed Java backend services and EDI integrations for SFTP-to-database enterprise workflows.
  • Implemented validation, parsing, persistence, and exception handling for recurring file-based integrations.
  • Improved stability through debugging, SQL analysis, unit testing, release support, and production issue resolution.

Projects

Focused, high-impact builds.

TriedTables

Full-stack restaurant recommendation platform with a Spring Boot API, React Vite UI, Firestore persistence, Google OAuth admin access, Google Places preview tooling, and Cloud Run deployment.

Visit website
Java 21Spring Boot 4React 19ViteMUIFirestoreGoogle OAuthCloud Run

Voice Conversation Microservice

Cloud Run backend that integrates Deepgram speech-to-text, OpenAI APIs for natural-language processing, and ElevenLabs text-to-speech for real-time conversational workflows.

JavaSpring BootCloud RunOpenAI APIsDeepgramElevenLabs

Document & Image Optimization Tools

Personal utilities for compressing PDFs, Word documents, and images, plus PDF-to-Word and Word-to-PDF conversion workflows for everyday document processing.

JavaAutomationPDF ToolsDocument Processing

Awards

Recognition for reliability and delivery.

15 Homer Awards

Platinum-level recognition at The Home Depot Canada for delivery, reliability, and engineering ownership.

Star of the Month / SPOT Awards

Recognized at Tata Consultancy Services for high-priority delivery and production support.

SPOT and Social Hero Awards

Recognized at Speridian Technologies for backend delivery, support, and team contribution.

Contact

Freelance inquiries

Let me know what you are building, your timeline, and the outcomes that matter most.