Couple Both Ways: bidirectional checks against silent drift

The coupling-check pattern: catching the drift between any two artifacts that are supposed to agree. A class diagram in my project claimed that two repository finders were each backed by a remote procedure call (RPC). Neither call existed. The diagram had been generated, reviewed, and committed, and it sailed through every check I had aimed at my diagrams, of which there were already three. It described a system slightly richer than the one I had actually built, and nothing flagged the differen...