Microservice Dependencies: How @requires Makes Them Explicit

Most microservice failures stem from invisible dependencies rather than architectural flaws. A taxonomy of seven coupling types is presented (domain, data, temporal, pass-through, common, contract, organizational), and GraphQL Federation's @requires directive is shown as a mechanism to make all of them explicit. With @requires, cross-service data dependencies move from hidden HTTP calls in application code into the schema itself, where they are validated at composition time, visible in query plans, and enforced at build time rather than discovered during production incidents. The post also covers @provides as a companion directive, warns against overusing it, and argues that correct service boundary design (one team, one service) is a prerequisite before any tooling can help.