When I started building UPVC Cloud, I had no idea it would end up processing billions in transactions across 15 companies. I thought it was a standard enterprise project. It turned out to be a two year lesson in what actually makes production software survive real business conditions. This is that lesson. What Is UPVC Cloud UPVC Cloud is a full scale cloud ERP built specifically for Pakistan's UPVC manufacturing and construction industry. It handles inventory, production orders, sales pipelines, customer management, invoicing, financial reporting, and HR workflows, all in one system. I built it from scratch at BuildSpark starting in late 2023. It is now live across 15 plus companies and processing a volume of financial transactions that I could not have predicted when I wrote the first line of code. The Stack and Why It Works The tech stack is Angular on the frontend and Node.js with NestJS on the backend, backed by PostgreSQL. Everything runs containerized on AWS.…