One wagon may travel alone, but a kingdom moves as a caravan. Beyond the Castle Gate: From Containers to Applications Packing a workshop into a container solves an important problem, but it does not solve the entire journey. In the previous chapter of The Kingdom in the Clouds, we explored how containers package an application together with the runtime, libraries, and dependencies it needs to operate consistently. That gives engineers a portable unit that can travel from a development machine to a test environment and eventually into production with far fewer surprises. Yet most modern applications are not single workshops sealed inside single wagons. They are collections of services, databases,…