What is schema design?

Example: A software architect joins a new company and inherits a codebase with no documentation, inconsistent naming, and tribal knowledge spread across a dozen engineers' heads. She does not start by writing code. She starts by constructing a schema: entity types, relationship maps, data flow diagrams, naming conventions. Her colleagues call this 'onboarding.' She calls it what it is — schema construction. Within two weeks, she can navigate the system faster than engineers who have been there for years. Not because she knows more facts. Because she has a better organizational structure for the facts she does know. Every subsequent decision she makes — refactoring, feature design, debugging — operates through that schema. The schema is not a byproduct of understanding. It is the mechanism of understanding.

This concept is part of Schema Foundations in the How to Think curriculum.