Deep modules: design the interface, delegate the implementation

Area: Architecture · Level: Advanced

Deep modules — small interface, rich internals — are the architectural shape that works best with agents: testable, easy to navigate, and delegable. This video shows how to split the work: you design the interface and delegate the implementation, treating each module as a gray box.

What you'll learn

• What makes a module "deep": a small interface over rich internals
• Why deep modules are more testable and easier to navigate
• How to divide the work: you design the interface, the agent implements
• What treating a module as a gray box — neither black nor white — means, and why it works
• How to delegate implementation with confidence once the interface is well designed

For whom

For advanced developers who design systems and want to delegate implementation to agents without losing control of the architecture. You'll get more out of it if you've already watched Why software fundamentals matter more than ever, where the idea of deep modules first appears.

After this video

Connect it with the written lesson The Big Idea — the 7 rules: that is where this design principle plugs into the course's complete working system, alongside the rest of the rules you apply in every session.