DRY Principle

DRY stands for “Don’t Repeat Yourself” - a software engineering principle that encourages uniqueness by introducing abstractions such as variables and functions to avoid redundancy in code.

Core Idea

The DRY principle aims to reduce repetition by:

• Creating reusable abstractions
• Extracting common patterns into functions or variables
• Maintaining a single source of truth for each piece of knowledge

When DRY Works Well

DRY is effective for:

• Application code that is tested
• Logic that truly represents the same concept
• Reducing maintenance burden through centralization

When DRY May Not Apply

Not all repetition is bad. Consider [[DAMP]] for:

• Configuration files
• Test code
• Cases where readability matters more than uniqueness

Related Concepts

• [[DAMP Principle]] - Alternative approach for configuration
• [[Source: Bazel BUILD Style Guide]]
• Code maintainability
• Software design principles