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Build a RAG System from Scratch: A Practical Tutorial

212AY Team·2026-04-10·20 min
from flask import Flask, request, jsonify

app = Flask(__name__)

@app.route('/query', methods=['POST'])
def query():
    data = request.json
    answer = query_rag(data['question'])
    return jsonify({'answer': answer})

if __name__ == '__main__':
    app.run(port=5000)

Next Steps

  • Add re-ranking for better retrieval
  • Implement hybrid search (keyword + semantic)
  • Add source citations to answers
  • Try different chunking strategies

Our "Build with LLMs" programme covers advanced RAG techniques and production deployment.

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