Compare Approaches

This skill guides you through systematically comparing different implementation approaches to inform decision-making.

Prerequisites

• Clear decision to be made
• 2 or more alternatives to compare
• Understanding of requirements and constraints

Steps

1. Define the Decision

## Decision: [What needs to be decided]

### Context
[Background and why this decision matters]

### Requirements
1. [Must-have requirement 1]
2. [Must-have requirement 2]
3. [Nice-to-have requirement]

### Constraints
- [Technical constraint]
- [Resource constraint]
- [Timeline constraint]

### Success Criteria
[How we'll know we made the right choice]

2. Identify Alternatives

List all viable options:

## Alternatives

### Option A: [Name]
**Description**: [Brief explanation]
**Precedent**: [Where this is used in codebase or industry]

### Option B: [Name]
**Description**: [Brief explanation]
**Precedent**: [Where this is used]

### Option C: [Name]
**Description**: [Brief explanation]
**Precedent**: [Where this is used]

3. Define Evaluation Criteria

Select relevant criteria:

4. Analyze Each Option

For each alternative, evaluate against criteria:

## Analysis: Option A - [Name]

### Implementation Approach
```go
// Example implementation
type ComponentA struct {
    // ...
}

func NewComponentA() *ComponentA {
    // ...
}

Performance

• Latency: [Assessment with evidence]
• Throughput: [Assessment]
• Memory: [Assessment]

Maintainability

• Complexity: [Assessment]
  • Lines of code: ~X
  • Cyclomatic complexity: Low/Medium/High
• Testability: [Assessment]
• Documentation: [Assessment]

Compatibility

• Existing patterns: [How it fits]
  • Similar to: pkg/example/ implementation
• Extensibility: [Future changes]
• Breaking changes: [Impact]

Operational

• Monitoring: [OTEL integration]
• Debugging: [Error visibility]
• Deployment: [Rollout considerations]

Pros

1. [Advantage 1]
2. [Advantage 2]

Cons

1. [Disadvantage 1]
2. [Disadvantage 2]

Risk Assessment

• [Risk 1]: [Likelihood] / [Impact]
• [Risk 2]: [Likelihood] / [Impact]

### 5. Create Comparison Matrix

```markdown
## Comparison Matrix

| Criteria | Weight | Option A | Option B | Option C |
|----------|--------|----------|----------|----------|
| **Performance** |
| Latency | High | ⭐⭐⭐ | ⭐⭐ | ⭐ |
| Throughput | Medium | ⭐⭐ | ⭐⭐⭐ | ⭐⭐ |
| Memory | Low | ⭐⭐ | ⭐ | ⭐⭐⭐ |
| **Maintainability** |
| Complexity | High | ⭐⭐⭐ | ⭐⭐ | ⭐ |
| Testability | High | ⭐⭐⭐ | ⭐⭐⭐ | ⭐⭐ |
| **Compatibility** |
| Existing patterns | High | ⭐⭐⭐ | ⭐⭐ | ⭐ |
| Extensibility | Medium | ⭐⭐ | ⭐⭐⭐ | ⭐⭐⭐ |
| **Weighted Score** | | **X.X** | **X.X** | **X.X** |

Legend: ⭐ = Poor, ⭐⭐ = Acceptable, ⭐⭐⭐ = Excellent

6. Analyze Trade-offs

## Trade-off Analysis

### Option A vs Option B
- **A is better when**: [Conditions]
- **B is better when**: [Conditions]
- **Key trade-off**: [Performance vs Flexibility, etc.]

### Critical Trade-offs
1. **[Trade-off 1]**: Choosing X means accepting Y
   - Impact: [Description]
   - Mitigation: [How to address]

2. **[Trade-off 2]**: ...

7. Make Recommendation

## Recommendation

### Primary Recommendation: Option [X]

**Rationale**:
1. [Reason aligned with highest-weight criteria]
2. [Reason aligned with requirements]
3. [Reason considering constraints]

**Conditions for this recommendation**:
- [Assumption 1]
- [Assumption 2]

### Alternative: Option [Y]

**When to choose this instead**:
- [Condition 1]
- [Condition 2]

### Not Recommended: Option [Z]

**Why not**:
- [Critical issue 1]
- [Critical issue 2]

### Implementation Notes
1. [Key consideration for implementing chosen option]
2. [Potential pitfall to avoid]
3. [Migration path if changing later]

8. Document Decision

## Decision Record

**Date**: [YYYY-MM-DD]
**Decision**: [Chosen option]
**Status**: [Proposed/Accepted/Deprecated]

### Context
[Brief background]

### Decision
We will use [Option X] because:
1. [Primary reason]
2. [Secondary reason]

### Consequences
**Positive**:
- [Benefit 1]

**Negative**:
- [Trade-off accepted]

**Neutral**:
- [Neither good nor bad]

### Follow-up Actions
- [ ] [Action 1]
- [ ] [Action 2]

Comparison Templates

Quick Comparison (2 options)

| Aspect | Option A | Option B |
|--------|----------|----------|
| [Criterion 1] | [Value] | [Value] |
| [Criterion 2] | [Value] | [Value] |

**Recommendation**: [Option] because [one-sentence reason]

Detailed Comparison (3+ options)

Use full template above with all sections.

Quality Checklist

• All options are viable (no strawmen)
• Criteria are weighted by importance
• Evidence supports assessments
• Trade-offs are explicit
• Recommendation has clear rationale
• Conditions for alternative are defined
• Implementation notes provided

Output

A comparison document with:

• Clear problem statement
• Comprehensive option analysis
• Weighted comparison matrix
• Trade-off analysis
• Actionable recommendation
• Decision record for future reference