Code Smell 273 – Overengineering

Keep It Simple, Stupid Overengineering complicates your code.

Problems

Unnecessary accidental complexity
Premature optimizations
Unnecessary abstractions
Poor Maintainability
Overly detailed designs
Slow iteration cycles
Bijection violation
Performance penalties

Solutions

Keep it Simple, Stupid
Simplify code paths
Minimize abstractions
Use the MAPPER as guidance to find abstractions
Focus on the core logic
Follow Occam’s razor by cutting away non-essential elements
Refactor regularly

Context

Overengineering happens when you build solutions that are too complex for your problem.

This happens when you create unnecessary layers of abstraction, use complex design patterns, or bloat your architecture making your code harder to maintain. When you overcomplicate your design, you risk introducing bugs and making your codebase difficult to navigate.

A simple problem like building an API doesn’t need the complexity of enterprise-level architecture if the goal is straightforward.

Some examples are the overuse of factories, excessive inheritance, or too granular interfaces when a simple approach would suffice.

Keeping things simple helps avoid creating code that is difficult to understand and maintain.

Sample Code

Wrong

// Overengineered approach
// with unnecessary factory and abstract layers
public abstract class PlanetCalculator {
public abstract double calculateDarkMatter(double mass);
}

public class TransneptunianCalculator extends PlanetCalculator {
@Override
public double calculateDarkMatter(double mass) {
// Complex, unnecessary steps for a simple calculation
double gravitationalConstant = 6.67430e-11;
double darkMatter = mass * gravitationalConstant * 0.25;
// Hypothetical calculation
return darkMatter;
}
}

public class PlanetCalculatorFactory {
public static PlanetCalculator getCalculator(String type) {
if (“Transneptunian”.equals(type)) {
return new TransneptunianCalculator();
}
throw new IllegalArgumentException(“Unknown calculator type”);
}
}

// Usage
PlanetCalculator calculator =
PlanetCalculatorFactory.getCalculator(“Transneptunian”);
double darkMatter = calculator.calculateDarkMatter(1000);

Right

// Simpler approach, without unnecessary factories and abstractions
public class DarkMatterCalculator {
public double calculateDarkMatter(double mass) {
return mass * 6.67430e-11 * 0.25; // Hypothetical calculation
}
}

// Usage
DarkMatterCalculator calculator = new DarkMatterCalculator();
double darkMatter = calculator.calculateDarkMatter(1000);

Detection

[x] Manual

This is a semantic smell.

You can detect overengineering by looking for excessive classes, methods, or features that do not contribute directly to solving the problem.

If you find yourself adding functionality that seems duplicated, unnecessary, or too complex, you likely have a case of over-engineering.

Level

[x] Intermediate

AI Generation

AI generators often introduce overengineering by suggesting patterns like factories or strategies where simpler solutions would work.

These patterns are useful but can lead to unnecessary complexity when applied to small or straightforward problems.

AI Detection

AI can help detect overengineered code by analyzing its structure and suggesting refactorings to simplify excessive abstractions or unnecessary layers. However, you still need human judgment to determine if the complexity serves a purpose or if you can simplify it.

Try Them!

Remember: AI Assistants make lots of mistakes.

Conclusion

Overengineering complicates your codebase and leads to maintenance headaches. Keep your designs simple, focus on solving your specific problem, and avoid unnecessary patterns and abstractions.