# Jay Gadhiya
Full-Stack AI Engineer: Backend, Cloud & LLM Systems. Ahmedabad, Gujarat, India.

I make LLM features dependable enough to ship.

Backend first, full-stack when the work needs it. I design the APIs, data models and guardrails that turn unpredictable model output into something a product can build on. Then I see it through to production.

- 2+ years: building production backends and AI systems
- Now: Software Developer, Full-Stack & AI at Vibgyor Technologies
- Domains: Healthcare, EdTech and e-commerce
- Latest: [Shipped Yaadi, an offline-first notes app](https://jaygadhiya.com/work/yaadi/)

## How I work
### Treat model output as untrusted input.
Each provider's response is normalised into one schema before the product uses it. Structured outputs keep the clinical agents' answers in a fixed format.

### Keep the vendor swappable.
Call sites never name a provider. One environment variable picks OpenAI, Gemini or Bedrock, so when a vendor's pricing or reliability changes, switching is a config change.

### Make speed a design input.
Response-time goals shaped the schemas from the start of a Spring Boot to FastAPI rewrite. Average API response time fell by about 50%.

### Own it all the way to production.
Schema, API, auth, tests and deploy: argon2 hashing, refresh-token rotation, 23 pytest tests against mocked AWS, and infrastructure defined in AWS SAM.

## Selected work
- [Multi-provider LLM platform](https://jaygadhiya.com/llms/work/multi-provider-llm-platform.md) (Vibgyor Technologies): Switch between OpenAI, Gemini and AWS Bedrock with one environment variable and zero code changes.
- [AI exam grading engine](https://jaygadhiya.com/llms/work/ai-exam-grading-engine.md) (Vibgyor Technologies): Grades answer sheets for 3+ exam boards and replaces hours of manual marking per batch.
- [Real-time healthcare agents](https://jaygadhiya.com/llms/work/real-time-healthcare-ai.md) (Vibgyor Technologies): Two real-time clinical agents. The diagnostic agent went through 4 versions.
- [Spring Boot to FastAPI](https://jaygadhiya.com/llms/work/spring-boot-to-fastapi-migration.md) (Vibgyor Technologies): Average API response time fell by about 50%.
- [Yaadi, an offline-first notes app](https://jaygadhiya.com/llms/work/yaadi.md) (Personal project, 2026): An installable notes app that works offline and syncs when it can, on a near-zero-cost serverless backend.

## Lab
Things I build for myself, in public.
- Yaadi (live): An offline-first notes app that syncs when it can, on a near-zero-cost serverless AWS backend. [Case study](https://jaygadhiya.com/work/yaadi/)

## Toolkit
- **Backend:** Python, FastAPI, SQLAlchemy, Pydantic, REST, WebSockets, Redis, APScheduler, pytest
- **AI and LLM:** OpenAI Agents SDK, OpenAI Realtime API, OpenAI Responses API + File Search, Gemini, AWS Bedrock, LangGraph, RAG, Vector stores, Prompt engineering
- **Cloud and DevOps:** AWS Lambda, DynamoDB, S3, Cognito, AWS SAM, SSM, Lightsail, Firebase, Docker and Docker Compose, GitHub Actions, Cloudflare
- **Security:** OAuth2 / OIDC, Okta SAML, JWT, Refresh-token rotation, Rate limiting
- **Data and integrations:** PostgreSQL, SQLite, Supabase, IndexedDB, Stripe, Authorize.Net, TaxJar
- **Frontend:** TypeScript, React, JavaScript

## Experience
### Software Developer, Full-Stack & AI, Vibgyor Technologies, Ahmedabad
Oct 2024 to now
Built the grading engine, the LLM platform, the healthcare agents and the FastAPI migration above. Also integrated Authorize.Net and TaxJar into an e-commerce SaaS backend with 10+ modules, deployed with Docker Compose on AWS Lightsail.

### Python Developer Intern, TRooTech, Ahmedabad
Jan to Aug 2024
Built FastAPI features with strict Pydantic validation, added OAuth2/OIDC and Okta SAML sign-in, and optimised SQL queries for API performance.

### B.E. in Information Technology, New LJ Institute of Engineering and Technology
2020 to 2024

## Writing
- [I didn’t want to pay for Obsidian Sync, so I built my own notes app on AWS for $0](https://medium.com/@gadhiyajay7676/i-didnt-want-to-pay-for-obsidian-sync-so-i-built-my-own-notes-app-on-aws-for-0-26b99925ba5f) (Medium, Oct 2026): Building Yaadi, an offline-first, open-source notes app, and the bug that taught me never to trust a phone’s clock.
- [I Asked 3 LLMs for JSON. I Got 3 Kinds of “JSON”.](https://medium.com/@gadhiyajay7676/i-asked-3-llms-for-json-i-got-3-kinds-of-json-794fd969289f) (Medium, Oct 2026): Making OpenAI, Gemini and Claude on AWS Bedrock behave like one provider in an AI grading system.

## Contact
Based in Ahmedabad, IST / UTC+5:30.
- Email: hello@jaygadhiya.com
- LinkedIn: https://www.linkedin.com/in/jaygadhiya-ai
- GitHub: https://github.com/gadhiyajay
- Résumé: https://jaygadhiya.com/Jay_Gadhiya_Resume.pdf