Nilava Chowdhury

About Me

Engineering leader with proven expertise in infrastructure & mobile development

I'm a Head of Engineering with expertise in infrastructure architecture, microservices, and mobile development. I led India's first Google Wallet metro card integration and large-scale government digital transformation projects serving millions of users daily.

My work spans high-scale infrastructure (Kubernetes, Node.js microservices), mobile apps (React Native with 100K+ downloads), and payment systems (Google Wallet NFC, PCI compliance).

Certifications & Partnerships

Google Partner - Tap & Pay

Google RCS Certified

CDAC Compliant

Infrastructure & Backend

Kubernetes Node.js PostgreSQL MongoDB Redis Kafka Istio AWS GCP

Mobile & Frontend

React Native React TypeScript Swift Java/Kotlin NFC ML Kit

DevOps & Tools

Docker ArgoCD Helm Prometheus Grafana ELK Stack CI/CD

Professional Experience

5+ years of engineering leadership and full-stack development

Head of Engineering

Billeasy

Feb 2025 - Present

Led engineering for major government projects including Metro QR ticketing and Maharashtra Ferry AFC system.

Pioneered India's first Google Wallet metro card solution with NFC Tap & Pay, achieving official Google Partner certification for closed-loop payment systems
Architected Kubernetes-based microservices handling millions of daily transactions across Mumbai, Hyderabad, Pune, and Nagpur metro networks with 99.99% SLA uptime
Built end-to-end Ferry AFC system with React Native validation app (ML Kit QR scanning), operator analytics dashboard, and WhatsApp ticket delivery via Meta Cloud API
Led Belgian Waffle Co./Tim Hortons migration from monolith to microservices, supporting 150 TPS during flash sales with zero downtime
Implemented comprehensive observability with Prometheus, Grafana, ELK stack, and custom incident management frameworks

Kubernetes Node.js React Native PostgreSQL Redis Kafka Istio Google Wallet Meta Cloud API

Technical Team Lead

udChalo

Aug 2023 - Jan 2025 • 1 yrs 9 mos

Led end-to-end development and launch of production-ready mobile app for armed forces personnel.

Built React Native app from scratch achieving 100K+ downloads and 4.5+ rating in 6 months
Integrated with major Indian flight providers (IndiGo, Air India), resulting in 30%+ increase in mobile bookings
Owned API integrations, secure payment workflows, and multi-environment CI/CD setup with product flavors
Mentored junior developers and conducted code reviews for high-quality releases aligned with business goals

React Native TypeScript Payment APIs CI/CD

Software Engineer

StepSetGo

May 2021 - Sep 2023 • 2 yrs 5 mos

Owned entire Fitness Vertical ensuring 98% accuracy in step counting and seamless health tracker integrations.

Developed Fitness Tracker integration (Fitbit, Garmin, Apple Watch) resulting in 50% increase in user adoption
Built microservices on Kubernetes (GCP/AWS) with 99.9% uptime and auto-scaling for growing demand
Implemented fraud detection algorithms for device shaking, reducing fraudulent steps by 90%
Ensured PCI compliance through tokenization for secure payment card storage
Wrote native code using React Native Bridge for step counting and background sync

React Native Kubernetes Node.js AWS/GCP

Application Developer

StepSetGo

Jun 2020 - May 2021 • 1 yr

Focused on security hardening and API optimization.

Implemented SSL Pinning on Android and iOS for secure server communication
Deployed Network Security Policy and App Signature Verifications
Implemented rate limiting on critical API routes to prevent abuse
Developed OTP API misuse prevention, significantly reducing fraud costs

Security Android iOS

Featured Projects

Large-scale infrastructure and mobile projects serving millions

Metro Digital Ticketing & Google Wallet NFC

India's First Wallet-Based Metro Card | Pan-India Metro Projects

Designed and deployed QR Ticketing infrastructure compliant with CDAC specifications across major metro networks. Pioneered Google Wallet NFC integration with mobile card emulation based on NXP standards (MIFARE/EMVco). Achieved Google Partner certification for closed-loop Tap & Pay.

Millions of daily rides with 99.99% uptime
Node.js microservices on Kubernetes
Cryptographically signed QR codes

Kubernetes Node.js Google Wallet NFC PostgreSQL

Ferry Automatic Fare Collection System

Maharashtra Government Project | Complete AFC Infrastructure

Built complete AFC system with payment gateway, UPI Intent, and WhatsApp ticket delivery. Developed React Native validation app with ML Kit QR scanning and offline-first architecture. Created operator dashboard with real-time analytics and Kafka-based report generation.

End-to-end fare collection system
99%+ ticket delivery via WhatsApp
Real-time operator analytics

React Native React ML Kit WhatsApp API Kafka

High-Scale E-Commerce Migration

Belgian Waffle Co. & Tim Hortons | Monolith to Microservices

Led complete migration from monolithic architecture to Kubernetes-based microservices. Achieved 150 transactions/second during National Waffle Day flash sale with zero downtime. Implemented event-driven architecture with Kafka for order processing and inventory.

150 TPS during flash sales
Zero downtime migration
Event-driven architecture

Kubernetes Kafka Redis PostgreSQL Spring Boot

udChalo Flight Booking App

Armed Forces Travel Platform | 100K+ Downloads

Built production-ready React Native app from scratch achieving 100K+ downloads and 4.5+ rating. Integrated with IndiGo, Air India APIs for real-time flight search and booking. Resulted in 30%+ increase in mobile bookings within 6 months of launch.

100K+ downloads in 6 months
4.5+ app store rating
30%+ mobile booking increase