Cloud
IRCTC PNR Status Notifier
Serverless PNR status tracker with automatic SMS/email alerts when waitlist clears.
PythonAWS LambdaEventBridgeSNSServerless
Compiling ideas into systems
Hi, I'mBitan Sarkar.
IIT Bhubaneswar · AWS Certified Solutions Architect · Publicis Sapient
Kolkata, India
~/bitan — livelive
$ whoami bitan-sarkar
$ stack Java · Spring WebFlux · AWS
nth prime
connecting…
—
biggest twin prime
(p, p+2)
—
Collatz · no loop ≤
searching for a counterexample
—
longest Collatz
record holder
— steps
this box never sleeps
0+
Years at Publicis Sapient
0+
LeetCode Rating
0+
LeetCode Problems Solved
AWS SAA
Solutions Architect
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.
DevTools
CloakVPN
Fully automated, GUI-powered VPN system. Terraform provisions OpenVPN EC2s across AWS regions, rotating IPs on demand.
PythonTerraformAWS EC2OpenVPNDevTools
Web Applications
Splitwise Clone
A full-stack expense sharing application with group management and debt simplification algorithms.
Full-StackExpense TrackingWeb DevelopmentAlgorithmsSelf-Hosted
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.