Duplication Quote by Robert C. Martin

““Duplication may be the root of all evil in software.””

Robert C. Martin

About This Quote

Source Book: Clean Code, Robert C. Martin, 2008

Duplicating code creates hidden dependencies and maintenance burdens, leading to systemic problems.

In simple terms: Copying code causes problems.

Key Takeaway

Avoid duplication, keep code DRY.

Themes

software design maintenance quality

Mood

analytical pragmatic

Type

technical advisory

When to use this quote

large codebases
team projects
refactoring
legacy systems

Key Concepts

DRY principle technical debt software evil

Questions to Reflect On

When is duplication justified?
How can you balance DRY with readability?

A Different Perspective

Duplication can sometimes be pragmatic for performance.

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