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Mussadiq Ali
Mussadiq Ali

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Building a RAG-Based AI Chatbot Backend with Node.js (Serverless)

Live API: https://matechs-backend.vercel.app/api/chat

Tech Stack: Node.js · RAG · Embeddings · Groq LLM · Vercel

🧠 Why RAG?

Instead of a generic chatbot that hallucinates, I wanted:

✅ Company-only answers

✅ No random AI output

✅ Controlled, safe responses

So I built a Retrieval-Augmented Generation (RAG) backend.

🏗️ System Architecture

Here’s the flow:

Company data stored in a knowledge base (text)

Data converted into embeddings

User query converted into an embedding

Cosine similarity used to find the best match

Matched context sent to an LLM

AI generates a response only from that context

📚 Knowledge Base

Company information includes:

Services

Projects

Target clients

Contact details

This ensures the chatbot:

Knows the business

Stays on-topic

Never hallucinates

🧬 Embeddings

Generated locally using @xenova/transformers

Stored as vectors

No paid embedding APIs

Works on free-tier hosting

This keeps costs at $0 for embeddings.

🤖 AI Generation

LLM: Groq (LLaMA-based)

Low temperature (less hallucination)

System prompt strictly enforces context usage

Confidence threshold fallback:

“I’ll connect you with our team”

☁️ Serverless Deployment

Backend deployed on Vercel

Uses serverless functions

Environment variables for API keys

CORS handled for frontend usage

Production-ready API

🔐 Safety & Reliability

No training on user data

No external data leakage

Context-restricted responses

Graceful fallback if confidence is low

🔗 Frontend Integration

The chatbot is fully connected to the frontend website and responds in real time.

👉 Try it live on the site:
https://matechssolutions.vercel.app/

🧩 Final Thoughts

This project demonstrates:

Real-world RAG implementation

AI + web integration

Serverless backend design

Production deployment practices

If you’re building safe AI chatbots for businesses, this pattern works extremely well.

About me

I’m a full-stack developer working on real-world web and AI systems, including RAG-based chatbots and production deployments.

🔗 Portfolio: https://mussadiqali15671.github.io/my-portfolio/

If you’re building something similar or want to discuss architecture, feel free to reach out.

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