16 — Anti-patterns

Driving question: When does a recurring solution become a recurring failure mode?

Learning objectives

• Distinguish anti-patterns from defects, smells, and disliked styles.
• Analyze the attractive short-term forces that create anti-patterns.
• Describe recovery paths rather than only naming problems.
• Recognize organizational/architectural feedback loops.

Anti-pattern anatomy

An anti-pattern is valuable when it explains:

• a recurring context;
• a tempting or common response;
• the negative consequences of that response;
• symptoms that reveal the problem;
• a refactored solution or recovery strategy.

Examples often discussed include Big Ball of Mud, God Object, Lava Flow, Golden Hammer, Spaghetti Code, and architecture-by-accumulation.

Why anti-patterns persist

They are often locally rational: deadlines reward short-term patches, ownership boundaries incentivize duplication, or frameworks make one mechanism unusually convenient. A useful recovery plan therefore considers socio-technical constraints as well as code structure.

Design / research exercise

For one anti-pattern, write the strongest possible argument for why a competent team would create it. Then design a staged recovery plan that does not assume a rewrite.

Suggested reading

• Brown et al., AntiPatterns.
• Foote & Yoder, “Big Ball of Mud.”