Available for opportunities

Full Stack Engineer - AI Systems

Sagar
Mandal

const role = "Full Stack & AI Engineer"

Full Stack Engineer at Techinterio, building RAG pipelines, Text-to-SQL engines, and enterprise HR SaaS. Based in Noida, India.

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tRPC Procedures

Employees Served

AI Prototype Chains

DB Tables (SQLite)

trpc-router.ts

01import { router, publicProcedure } from "./trpc"

02import { z } from "zod"

04export const appRouter = router({

05getInvoice: publicProcedure

06.input(z.string())

07.query(async ({ input }) => {

08// RAG -> Text-to-SQL pipeline

09return await rag.query(input);

10}),

11});

13export type AppRouter = typeof appRouter

AI_ENGINE_READY

RAG Pipelines

Text-to-SQL

LlamaIndex

NVIDIA NIM LLM

tRPC

FastAPI

TypeScript

React 18

Socket.io

MongoDB

Docker

AWS EC2

Casbin RBAC

Turborepo

Pydantic v2

SSE Streaming

RAG Pipelines

Text-to-SQL

LlamaIndex

NVIDIA NIM LLM

tRPC

FastAPI

TypeScript

React 18

Socket.io

MongoDB

Docker

AWS EC2

Casbin RBAC

Turborepo

Pydantic v2

SSE Streaming

Expertise

What I build

AI & LLM Systems

End-to-end RAG pipelines, Text-to-SQL engines with semantic layers, intent classifiers, hallucination mitigation stacks, and real-time SSE token streaming. Powered by NVIDIA NIM, LlamaIndex, and FastAPI.

RAG PipelinesText-to-SQLLlamaIndexNVIDIA NIMFastAPIPydantic v2OCR / LlamaParse

Enterprise Full-Stack SaaS

Production-grade monorepo platforms with end-to-end type safety, real-time WebSocket communication, multi-role RBAC, CI/CD pipelines, and cross-platform mobile delivery from a single codebase.

React 18 + TypeScripttRPC v11Casbin RBACSocket.ioTurborepoMongoDBDocker + AWS EC2

Work

Selected projects

Enterprise SaaS

TISuite

HR & Expense Management Platform

Production HR SaaS serving 400+ employees. 93 end-to-end type-safe tRPC procedures, 429 UI components, Casbin RBAC with 4 role tiers, full audit logging, and real-time bidirectional chat via Socket.io.

React 18TypeScripttRPC v11Socket.ioCasbinMongoDBTurborepoDockerCapacitor

AI / LLM

Invoice Intelligence

RAG + Text-to-SQL for B2B Procurement

6-step Text-to-SQL pipeline with governed semantic layer. 3-tier hybrid NLU classifier (~40 intents), multi-backend PDF OCR, real-time SSE streaming, and multi-layer hallucination mitigation.

FastAPILlamaIndexNVIDIA NIMLlamaParsePydantic v2SQLAlchemyDoclingSQLite

Open Source

Santra CLI

AI Coding Assistant - Mar 2026

Open-source AI CLI coding assistant with Bun and TypeScript supporting code generation, refactoring, and prompt management. Companion Next.js web interface with real-time prompt editing.

BunTypeScriptInkNext.jsTurborepoTailwind CSS 4

Full-Stack

Rental Property System

Airbnb-style Platform - Feb 2026

Full-stack rental platform with 40+ listings, calendar-based booking, Leaflet/Google Maps integration, Recharts analytics, PostHog tracking, and JWT auth backed by MongoDB.

React 18TypeScripttRPCTanStack QueryMongoDBLeafletPostHog

E-Commerce

Saan Makhana

Headless E-Commerce - Jan 2026

Headless e-commerce platform with 15+ product SKUs, cart, and checkout. Next.js frontend connected to Shopify headless CMS via REST API with full TypeScript coverage and Zod validation.

Next.jsTypeScriptShopifyZodTailwind CSSReact Hook Form

Full-Stack

Startup Social Platform

Investor Matching - 2023

Social media platform for fundraising with post feeds, investor matching, community engagement, and real-time notifications. Page load times under 2 seconds with full TypeScript coverage.

Next.jsNode.jsMongoDBTailwind CSSZodTypeScript

Toolkit

Technical skills

Languages

TypeScriptPythonJavaScriptSQL

Frontend

React 18Next.jsTailwind CSSTanStack QueryRedux ToolkitRadix UIFramer MotionZod

Backend & APIs

tRPC v11FastAPINode.jsExpressPydantic v2Socket.ioRESTSSE StreamingJWT

AI & ML

RAG PipelinesText-to-SQLLlamaIndexNVIDIA NIMLlamaParseDoclingBM25OpenAI SDKOllama

Databases & ORM

MongoDBSQLitePostgreSQLMySQLRedisMongooseSQLAlchemyPrisma

DevOps & Tools

DockerTurborepoCircleCIAWS EC2AWS S3VitestpytestMSWViteBun

History

Work experience

Techinterio Private Limited

Full Stack Engineer

Noida, Uttar Pradesh

Sep 2023 - Present

Architected TISuite, a production-grade enterprise HR & Expense SaaS serving 400+ employees across attendance, leave, expense, and performance modules.
Designed a fully type-safe API layer with 93 tRPC procedures, 429 UI components across 30 routes, and 24+ Mongoose models for full-stack data consistency.
Implemented Casbin RBAC with 4 role tiers and full audit logging; real-time bidirectional chat via Socket.io 4 with JWT authentication.
Engineered a 6-step Text-to-SQL pipeline with a governed semantic layer and 3-tier hybrid NLU intent classifier (~40 intents) powered by NVIDIA NIM LLM + LlamaIndex RAG, reducing report generation time by 60%.
Built a RAG invoice intelligence API (async FastAPI, Pydantic v2, 14-table schema) with multi-backend PDF OCR, multi-layer hallucination mitigation, and real-time SSE token streaming.

Techinterio Private Limited

Full Stack Developer Intern

Noida, Uttar Pradesh

Jun 2023 - Aug 2023

Developed a social media platform for fundraising and startups with post feeds, investor matching, and real-time notifications using Next.js, Node.js, and MongoDB.
Achieved page load times under 2 seconds with full TypeScript coverage, plus Tailwind CSS, Zod schema validation, and React Hook Form throughout.

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