Improve Codebase Architecture

Find architectural friction the way a future maintainer or coding agent experiences it. Favor deep modules: a small interface hiding substantial implementation complexity. The deep-module idea comes from Ousterhout's A Philosophy of Software Design — use it as the bar for "is this module worth carving out," not as decoration.

Read $SKILL_DIR/references/deepening-guide.md before classifying dependencies, judging test strategy, or drafting the RFC.

Workflow