Builders from across India came together for Convolve 4.0 - A Pan IIT AI/ML Hackathon, hosted by IIT Madras, to develop impactful, real-world AI systems across critical domains. The hackathon focused on multi-agent systems, retrieval-augmented generation (RAG), vector memory, multimodal intelligence, and production-ready AI pipelines. Participants built solutions spanning healthcare and medical reasoning, disaster response and crisis intelligence, climate and risk monitoring, legal-tech and governance systems, misinformation detection, public safety, infrastructure auditing, education, and…