codemod-generator

Codemod Generator Skill

Overview

This skill generates automated code migration scripts (codemods) that transform consumer code to use new API versions, reducing the burden of SDK upgrades on developers.

Capabilities

• Create AST-based code transformations
• Support multiple languages (JavaScript, TypeScript, Python, Go)
• Provide dry-run mode with change preview
• Implement safe rollback mechanisms
• Generate detailed migration reports
• Handle edge cases and partial migrations
• Support interactive migration modes
• Validate transformations with tests

Target Processes

• Backward Compatibility Management
• Package Distribution
• SDK Versioning and Release Management

Integration Points

• jscodeshift for JavaScript/TypeScript
• libcst for Python
• go-codemod for Go
• Rector for PHP
• Custom AST transformers

Input Requirements

• Source and target API versions
• Transformation rules specification
• Test cases for validation
• Edge case handling requirements
• Rollback strategy

Output Artifacts

• Codemod scripts per language
• Dry-run reports
• Migration validation tests
• Edge case documentation
• CLI wrapper for execution
• Rollback scripts

Usage Example

skill:
  name: codemod-generator
  context:
    sourceVersion: "1.x"
    targetVersion: "2.0"
    languages:
      - typescript
      - python
    transformations:
      - type: methodRename
        from: oldMethod
        to: newMethod
      - type: parameterChange
        method: createResource
        changes:
          - name: config
            wrap: options
    dryRun: true
    generateTests: true

Best Practices

1. Always provide dry-run mode first
2. Generate comprehensive change reports
3. Handle partial migrations gracefully
4. Include rollback capabilities
5. Test codemods against real codebases
6. Document manual intervention cases