Certificate

# Design patterns certificate - outline

## Part 1 - multiple choice (25 questions, 45 min)

Topics:
- Creational: Factory, Builder, Singleton, Prototype
- Structural: Adapter, Decorator, Composite, Facade, Proxy
- Behavioural: Strategy, Observer, Command, State, Template Method, Visitor
- When NOT to apply a pattern (anti-pattern detection)

Passing mark: 70 percent.

## Part 2 - refactor project (take-home, ~6 hours)

Pick an open-source project (or your own) with a known smell:

- A switch or chain of if/else that begs for Strategy
- A god class that needs Facade or extraction
- A hand-rolled event system that should be Observer
- A complex constructor that needs Builder

Submit:
- A PR (real or mock) that applies the pattern
- A 1-page write-up: why this pattern, what it earns, what it costs
- A test or benchmark proving you did not regress behaviour

## Grading

- Pattern choice fit (35 percent)
- Code quality (25 percent)
- Write-up clarity (25 percent)
- Tests + measurable outcome (15 percent)

## Tips

- The strongest submissions delete more code than they add
- A pattern that is wrong for the codebase but applied 'cleanly' will not score well
- 'Just a function' is a valid finding - say so

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