codebase-design

Design codebase modules with small interfaces and large implementations.

Updated Jul 2, 2026

Search Tags:#testability #interface design #deep modules #code design #module refactoring

Ready to run

npx skills add https://github.com/tgmarinho/agent-super-powers-matt-pocock-skills-comparasions --skill codebase-design-tgmarinho

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: codebase-design
Source: https://github.com/tgmarinho/agent-super-powers-matt-pocock-skills-comparasions/tree/main/upstream-snapshots/mattpocock-skills/skills/engineering/codebase-design
Command: npx skills add https://github.com/tgmarinho/agent-super-powers-matt-pocock-skills-comparasions --skill codebase-design-tgmarinho

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill helps users design and improve module interfaces, identify deepening opportunities, and decide where seams should be placed, making code more testable and AI-navigable.

Core Features & Use Cases

Deep Module Design: Create modules with a small interface and a large implementation, improving leverage and maintainability.
Seam Placement: Decide where to place the seam for altering behavior without editing the module.
Testability: Enhance testability by focusing on observable outcomes through the interface.
Use Case: When designing a new module or refactoring an existing one, use this Skill to define the interface, implement the module, and ensure it's testable.

Quick Start

Use the codebase-design skill to design a new module for your codebase, focusing on minimizing the interface and maximizing leverage.

Frequently Asked Questions about codebase-design

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

What is a deep module in codebase design?▼

A deep module in codebase design features a small interface paired with a large implementation. This structure maximizes leverage by hiding complexity, which improves maintainability and makes the code more testable.

How do I refactor an existing module to improve testability?▼

To improve testability through module refactoring, place seams where behavior can be altered without editing the module. Focus on observable outcomes through a minimized interface to isolate functionality for testing.

Where should I place seams when designing module interfaces?▼

Seam placement should target areas where you need to alter behavior without modifying the module internals. Position seams at interface boundaries to isolate dependencies and ensure testability through observable outcomes.

How do I design a new module interface to maximize leverage?▼

Design a new module interface by minimizing its surface area while maximizing the implementation behind it. This deep module approach hides complexity, improves maintainability, and makes the codebase easier to navigate.

Do I need prior knowledge of module design principles to use deep modules?▼

Yes, understanding module design principles and best practices is required. The process focuses on advanced interface design, deep structures, and seam placement, demanding familiarity with software engineering concepts.

Why does minimizing a module interface make code more maintainable?▼

Minimizing a module interface reduces the surface area exposed to the rest of the codebase, creating a deep module. This hides implementation complexity, isolates changes, and results in higher leverage and better maintainability.