So I work for a very large company, and there's many projects going on throughout the business. This only describes one particular project, but the entire system is a multi-billion £ business, and this project is replacing the customer-facing part of the system, so it will ultimately serve hundreds of thousands, possibly millions of customers. There are about 30-40 projects in the business that I know of, and there about 25 infrastructure/platform engineers working on these projects.