Cloud
IRCTC PNR Status Notifier
Serverless PNR status tracker with automatic SMS/email alerts when waitlist clears.
PythonAWS LambdaEventBridgeSNSServerless
Open to senior engineering roles
Hi, I'mBitan Sarkar.
IIT Bhubaneswar · AWS Certified Solutions Architect · Publicis Sapient
Kolkata, India
~/bitan — zsh
$ whoami
bitan-sarkar
$ cat role.txt
Software Engineer @ Publicis Sapient
$ stack --list
Java · Spring WebFlux · AWS · Python
$ scale
1,000,000+ telecom subscribers served
0+
Years at Publicis Sapient
0+
LeetCode Problems Solved
AWS SAA
Solutions Architect
0M+
Telecom Subscribers (Omantel)
The stack I build with
JavaSpring BootSpring WebFluxAWSPythonGoNode.jsDockerKubernetesTerraformDynamoDBGraphQLRedisMongoDBLambdaCognitoJavaSpring BootSpring WebFluxAWSPythonGoNode.jsDockerKubernetesTerraformDynamoDBGraphQLRedisMongoDBLambdaCognito
Selected Work
Featured Projects
A few things I've built and shipped — from serverless tooling to system-design write-ups.
Backend
Scalable URL Shortener
Production-grade URL shortener design on AWS Lambda + MongoDB with a widely-read LinkedIn article.
System DesignAWS LambdaMongoDBCloudFrontNode.js
DevTools
CloakVPN
Fully automated, GUI-powered VPN system. Terraform provisions OpenVPN EC2s across AWS regions, rotating IPs on demand.
PythonTerraformAWS EC2OpenVPNDevTools
What I Do
Three things I do well
Backend Engineering
Reactive microservices with Spring WebFlux. High-throughput APIs. Authentication systems (SAML, OIDC, Cognito). Built for production scale.
Cloud & AWS
Lambda, API Gateway, DynamoDB, Cognito, EventBridge, CloudWatch, S3, CloudFront. AWS SAA certified. Infrastructure as code with Terraform.
System Design
URL shorteners, auth architectures, serverless pipelines. I document architectural decisions — my URL shortener article has been widely read on LinkedIn.