improve-codebase-architecture

Refactoring messy codebases requires identifying deepening opportunities that reduce shallow-module complexity and concentrate logic behind smaller, testable interfaces. This Skill analyzes dependencies and applies a deletion test to guide refactors toward minimal unnecessary indirection.

A deep module in software architecture hides maximum complexity behind a minimal interface. You create one by identifying shallow modules across your codebase, categorizing their dependencies, and reshaping seams to concentrate logic so testing and navigation require fewer module bounces.

Designing seams and adapters requires classifying dependencies as in-process, local-substitutable, remote but owned, or true external. This categorization determines the safest testing strategy and seam shape, ensuring tests survive internal refactors without unnecessary indirection.

The best way to plan a codebase refactoring is an exploration-first workflow that categorizes dependencies and runs a deletion test before modifying code. This crystallizes constraints and ensures tests survive internal refactors by guiding changes toward testable interfaces.

Yes, this approach explicitly handles true external dependencies by classifying them separately from in-process and local-substitutable ones. This classification determines the safest testing strategy and seam shape, ensuring external integrations remain stable during architectural deepening.