modular-design-principles
Modular Design Principles
Use this skill when reasoning about structure and boundaries in any codebase. It intentionally avoids framework names, folder conventions, and tooling — map principles to your stack locally.
What to load
| Task | Where |
|---|---|
| Principles table + violations + workflows (this file) | SKILL.md |
| Per-principle definition, agent rules, abstract examples | references/principles.md |
Layered mental model
- Composition roots (applications, hosts, runners): wire modules together; keep orchestration thin.
- Modules / bounded contexts: cohesive units of behavior and data ownership; each should be understandable and testable on its own.
- Shared kernels (use sparingly): only stable, truly cross-cutting concepts; resist turning them into a grab-bag of “everything everyone needs.”
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