The uk government development service as you call it is not a service. It’s more of a declaration of process that is adhered to across diverse departments and organisations that make up the government. It’s usually small teams that are responsible for exploring what a service is or needs and then implementing it. They are able to deliver decent services because they start small, design and user test iteratively and only when there is a really good understanding of what’s being delivered do they scale out. The technology is the easy bit.