business-logic-entry-point-one-per-module
One Entry Point per Module for Business Logic
Goal
Every business-logic entry point must be a separate module. Do not group multiple entry points together in the same class, object, or file because they operate on the same domain entity type.
A module here means the unit of code organization provided by the language: a file, a single-class file, a single-object file, or equivalent. Each entry point gets its own.
What Counts as In Scope
Apply this skill to code that does one or more of these things:
- defines multiple business-logic entry points in a single class, object, or file
- groups command handlers, query handlers, use cases, or application services by domain entity type into a shared container
- introduces a service class or facade that bundles several business operations as methods on one object
- organizes business-logic entry points by entity rather than by operation
The Rule
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