Tony Meyn (Umbraco India User Group) traces Umbraco’s 21‑year evolution from single‑server XML storage to modern, scalable load‑balanced architectures (v15–v17+). He explains hybrid caching (L1/L2, Redis), output caching, SignalR challenges, centralized logs/search/media, and developer responsibilities for writing stateless, distributable code and using Umbraco Cloud.