Pattern Clinic

Students receive a design problem and compare at least two candidate patterns plus a non-pattern alternative.

Required reasoning

For each alternative:

• context and forces;
• dependency changes;
• expected future changes;
• effect on testability/understandability;
• implementation/migration cost;
• failure mode if the prediction about future change is wrong.

The winning design is the one best supported by the stated forces—not the one with the most recognized pattern names.