Codebase Design

This gives Claude a precise vocabulary for designing modules with small interfaces and large implementations. It's built around John Ousterhout's idea of depth but tweaked to measure leverage instead of line ratios. You'd reach for this when deciding where to put a seam, whether to extract an interface, or how to make something more testable. The glossary is strict about terms like "module" and "seam" instead of letting "component" or "boundary" slip in, which actually matters when you're trying to think clearly about structure. It includes the deletion test: imagine removing the module and see if complexity vanishes or just spreads across callers. Pairs with additional patterns for deepening clusters and exploring alternative interface designs.

Install to Claude Code

npx -y skills add mattpocock/skills --skill codebase-design --agent claude-code