I’ve worked on projects designed by architects. They had big, beautiful interfaces defined by types. When I implemented the interfaces, working systems magically appeared. But it was my job to implement the interfaces. They didn’t get organic adoption from other engineers. Nobody was voluntarily choosing to implement their system via the big beautiful interface. These projects ultimately failed.

Projects I’ve worked on that succeeded had small, comprehensible interfaces. Engineers can quickly understand how to use them and see what the benefits are. The pitch is “our service does this one thing you need,” not “build your entire project by implementing the interface of our type-safe general data processing system.”