name	migrating-rules
description	Helps migrate code when updating to new rule versions. Compares rule versions from the index and generates migration plans. Use when rules are updated or when migrating between framework versions.

Migrating Rules - Helps migrate code when rules are updated or when switching between framework versions by comparing rule differences. - Rules are updated to new versions - Migrating from one framework to another (e.g., Next.js 14 → 15) - Updating coding standards - User asks "How do I update my code for the new rules?" - Rule changes require code modifications

Step 1: Identify Migration Context

Determine what needs migration:

Rule version update: Same framework, updated rules
Framework migration: Different framework (e.g., Pages Router → App Router)
Standard update: Coding standards changed
Technology change: New technology added to stack

Step 2: Load Rule Index

Load the rule index to find relevant rules:

@.claude/context/rule-index.json

Step 3: Identify Source and Target Rules

Find the rules involved in migration:

Source rule: Current rule being used
Target rule: New rule to migrate to
Both rules: If migrating between frameworks

Step 4: Load Rule Files

Load both source and target rule files:

Read source rule file
Read target rule file
Compare differences

Step 5: Analyze Differences

Compare rules to identify:

Removed patterns: What's no longer allowed
New patterns: What's now required
Changed patterns: What's been modified
Breaking changes: Incompatible changes

See reference/migration-patterns.md for common migration patterns.

Step 6: Generate Migration Plan

Create step-by-step migration plan:

Inventory: List all files affected
Priority: Order of migration (critical first)
Steps: Specific code changes needed
Verification: How to verify migration success

1. **Be Comprehensive**: Identify all affected code 2. **Prioritize**: Critical changes first 3. **Show Examples**: Before/after code for each change 4. **Step-by-Step**: Break complex migrations into clear steps 5. **Verify**: Include verification steps **Migration Plan Format**

Structure migration plan clearly:

## Migration Plan: [Source] → [Target]

**Migration Type**: [Rule update / Framework migration / Standard update]
**Affected Files**: [count]
**Estimated Effort**: [low/medium/high]

### Overview

**Source Rule**: [rule name and path]
**Target Rule**: [rule name and path]
**Key Changes**: [summary of main differences]

### Breaking Changes

#### [Change 1]
**Impact**: [high/medium/low]
**Description**: [what changed]

**Before**:
\`\`\`[language]
[old code pattern]
\`\`\`

**After**:
\`\`\`[language]
[new code pattern]
\`\`\`

**Migration Steps**:
1. [Step 1]
2. [Step 2]
3. [Step 3]

---

### New Requirements

#### [Requirement 1]
**Description**: [new requirement]

**Action Required**:
[What needs to be done]

**Example**:
\`\`\`[language]
[code example]
\`\`\`

---

### Deprecated Patterns

#### [Pattern 1]
**Status**: Deprecated
**Replacement**: [new pattern]

**Migration**:
\`\`\`[language]
// Old (deprecated)
[old code]

// New (recommended)
[new code]
\`\`\`

---

### Migration Checklist

- [ ] Step 1: [action]
- [ ] Step 2: [action]
- [ ] Step 3: [action]
- [ ] Verification: [how to verify]

### Verification

[How to verify migration is complete and correct]

**Common Migration Scenarios**:

Next.js 14 → 15:

App Router changes
React 19 features
Server Component patterns

Pages Router → App Router:

Route structure changes
Data fetching patterns
Layout changes

TypeScript Strict Mode:

Type safety improvements
any → proper types
Null checking

Python 3.10 → 3.12:

Type hint improvements
Pattern matching
Performance optimizations

For each scenario, see migration-patterns.md for detailed patterns.

migrating-rules

Install Skill

SKILL.md