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CASE STUDY2026Full-stack / AI Integration

RAG Assistant

Localized AI document Q&A system with OCR extraction and vector similarity search.

React 19Tailwind CSSDjango REST FrameworkPythonLangChainFAISSOllamaTesseract OCRPyPDF
RAG Assistant AI Document Q&A Interface

// CONTEXT & OBJECTIVE

RAG Assistant is a document Q&A application that runs on local servers, eliminating reliance on third-party cloud AI APIs.

The system processes uploaded documents, segments text into semantic chunks, generates vector embeddings, and feeds retrieved context to a local LLM to generate grounded answers.

// SYSTEM ARCHITECTURE

Data Pipeline & Architecture Overview

STEP 01

Upload & Extraction

Accepts PDF/DOCX/Images, extracting text content via PyPDF and Tesseract OCR.

STEP 02

Chunking & Embedding

RecursiveCharacterTextSplitter creates 1000-char chunks and embeds via nomic-embed-text.

STEP 03

FAISS Vector Indexing

Stores embeddings in FAISS Index for rapid vector similarity retrieval.

STEP 04

Retrieval & Inference

Retrieves top matching context chunks and synthesizes response via Ollama Qwen2.5:7B.

// ENGINEERING CHALLENGES

Key Engineering Hurdles & Solutions

CHALLENGE 01

Multi-format Document Text Extraction

Coordinated PyPDF for native digital documents alongside Tesseract OCR for image-based scans.

CHALLENGE 02

Balancing Chunk Size and Overlap

Configured 1000-character chunks with 150-character overlap to preserve semantic context across chunk boundaries.

// RESULTS & TAKEAWAYS

Measurable Outcomes & Learnings

>Successfully built an end-to-end RAG pipeline operating entirely on local hardware.
>Provided accurate, context-grounded document question answering.
>Zero third-party API costs with complete local data sovereignty.