Rishav Raj

“Curiosity is the key to problem solving, keep asking questions.”

I am a problem solver based in Hyderabad, currently at Evernorth Health Services, part of the Cigna Group. I take things end to end: system design, POC, UI, backend, cloud infra, POC scale to enterprise load. Solo or in a team.

Lately that has meant getting a language model to answer real questions from a company's own documents, and showing where the answer came from.

Before this, Flexday AI. Studied at IIT Madras.

Products

infraviz Architecture docs that cite their sources — every claim carries an exact substring from a real file.

All products.

Writing about work I have done

A product chatbot, and the pipeline that feeds it Crawling a Salesforce knowledge base, then getting a model to answer from it without guessing.
An RBAC service for clients on three different clouds Why we built our own instead of using AWS IAM or Entra, and what that cost.
A reels feed you can order from Social commerce for local brands, where what can reach you decides the feed.
Kureita, a node based AI video studio Wire generation nodes on a canvas and a runner walks the graph in order.

A handful of write-ups, I will add more as I find time.

System design

Designing a chat application Delivery guarantees, fanout for group chats, presence, and why WhatsApp moved off a thread per connection.
Designing a media service Presigned uploads, thumbnail generation without a queue service, and why file storage is a separate service from the chat app that uses it.

Working notes on system design, mostly for me. All notes.

What I work with

Search and AI

Retrieval pipelines end to end, crawling and parsing a corpus, chunking, hybrid and graph search, re ranking, evals, guardrails. Azure AI Search, Weaviate.

Backend

Python, FastAPI, Node.js, TypeScript, MongoDB, PostgreSQL, Redis, Elasticsearch.

Infrastructure

AWS, Terraform, ECS Fargate, Lambda, Docker, GitHub Actions, Auth0, Okta.

System design

Rate limiting, caching and invalidation, idempotency, queues for load levelling, sharding and replication, consistency trade offs.

Education

2019 to 2023

B.Tech, IIT Madras.

Bit of personal life

Most days

Gym, runs, cycling. This is the part I do not skip.

Sports

Badminton and swimming, when I want it to feel less like training.

With people

Run clubs, cycling groups, weekend treks, marathons when the calendar allows.

Pending

Hyrox. Missed it this time, which still bothers me.

Travel

Road trips, long rides on the bike, long drives in the car.

If any of this is your thing, tell me. I always enjoy the company.

Resume, GitHub, LinkedIn. I am open to backend and AI engineering roles. Reach out if that is useful to you.