Open to opportunities

Rohan User

@rohanuser9

Message

I build secure, high-scale serverless microservices and AI-powered RAG systems on AWS.

India

Message

What I'm looking for

I’m looking to own cloud backend and platform security end-to-end—shipping serverless microservices, optimizing latency and cost, and building production-ready AI/RAG features with strong availability, observability, and performance.

I’m a Cloud & Backend Engineer specializing in high-scale, secure, serverless microservices platforms. At BT Group – Openreach, I helped migrate 17/45+ legacy applications to AWS Lambda/API Gateway and delivered 60% cold-start latency reduction, 65% cloud cost savings, and 99.95% availability across distributed multi-service systems.

I focus on defense-in-depth platform security and end-to-end ownership—from architecture to production. I designed a centralized Lambda Authorizer with dual authentication (Custom JWT + Azure AD JWT/OIDC with RSA-encrypted headers), re-architected Spring Boot to Quarkus to improve startup time, and built CI/CD and observability using CloudWatch. I also build LLM-powered RAG systems (FastAPI + FAISS) and have implemented local-GPU deployments using Mistral 20B for real-time recommendations.

Experience

Work history, roles, and key accomplishments

Current

Cloud Engineering Professional

Current

BT Group (Openreach)

Aug 2024 - Present (1 year 10 months)

Migrated 17/45+ legacy applications to an AWS serverless platform (API Gateway + Lambda + Quarkus), supporting REST, SOAP, and SES workflows. Reduced auth latency to 80–120ms (warm), cut cold-start latency by 60%, and lowered cloud OpEx by 65% via re-architecture and platform/security optimizations.

AWS Lambda API Gateway AWS SAM Quarkus Azure AD Microservices Cloudwatch CI CD

Software Development Intern

BT Group (Openreach)

Jan 2024 - Jul 2024 (6 months)

Migrated Spring Boot services to Quarkus, improving startup time by 40%. Implemented circuit breakers and retry logic to meet a 2s SLA and built high-throughput SOAP integrations handling 5,000+ RPM.

Quarkus Spring Boot SOA Integration Circuit Breakers Retry Logic Microservices Performance Optimization

Remote Project Intern

HPCC Systems

Sep 2022 - Aug 2023 (11 months)

Built a distributed tensor processing pipeline for large-scale image data, embedding Python (NumPy) into ECL and developing multi-node tensor resizing/stacking libraries. Won 1st place among 45 teams in a hackathon, leading to internship conversion.

Distributed Computing Python NumPy Multi Node

Education

Degrees, certifications, and relevant coursework

R.V. College of Engineering

Bachelor of Engineering, Computer Science and Engineering

2020 - 2024

Activities and societies: Team Antariksh Avionics Subsystem Lead; led fault-tolerant avionics system design for sounding rockets and conducted workshops on flight computers, telemetry, and parachute deployment systems.

B.E. in Computer Science and Engineering at R.V. College of Engineering (2020–2024).