Plan Implementation

Methodology for decomposing work into implementation units and planning each one. Use this skill standalone or as a reference from other planning skills.

Decomposition

Sizing

• One unit = one logical unit of work (a feature, a subsystem, a layer)
• Never split tightly-coupled pieces across units (if UI + API + tests are inseparable, keep them together)
• Split independent subsystems into separate units
• If a unit would touch more than ~15-20 files or span 3+ unrelated subsystems, split further
• If the entire scope fits one session, produce a single unit — do not over-decompose
• Each unit must leave the codebase fully integrated — never leave components unreachable from the project's entry points

Ordering

Order by dependency — foundational work before dependent work: