/migrate-to-typescript

Migrate to TypeScript

Migrate JavaScript project to TypeScript

Instructions

1. **Project Analysis and Migration Planning**

• Analyze current JavaScript codebase structure and complexity
• Identify external dependencies and their TypeScript support
• Assess project size and determine migration approach (gradual vs. complete)
• Review existing build system and bundling configuration
• Create migration timeline and phased approach plan

2. **TypeScript Installation and Configuration**

• Install TypeScript and related dependencies (@types packages)
• Create comprehensive tsconfig.json with strict configuration
• Configure path mapping and module resolution
• Set up incremental compilation and build optimization
• Configure TypeScript for different environments (development, production, testing)

3. **Build System Integration**

• Update build tools to support TypeScript compilation
• Configure webpack, Vite, or other bundlers for TypeScript
• Set up development server with TypeScript support
• Configure hot module replacement for TypeScript files
• Update build scripts and package.json configurations

4. **File Migration Strategy**

• Start with configuration files and utility modules
• Migrate from least to most complex modules
• Rename .js files to .ts/.tsx incrementally
• Update import/export statements to use TypeScript syntax
• Handle mixed JavaScript/TypeScript codebase during transition

5. **Type Definitions and Interfaces**

• Create comprehensive type definitions for project-specific types
• Install @types packages for external dependencies
• Define interfaces for API responses and data structures
• Create custom type declarations for untyped libraries
• Set up shared types and interfaces across modules

6. **Code Transformation and Type Annotation**

• Add explicit type annotations to function parameters and return types
• Convert JavaScript classes to TypeScript with proper typing
• Transform object literals to typed interfaces
• Add generic types for reusable components and functions
• Handle complex types like union types, mapped types, and conditional types

7. **Error Resolution and Type Safety**

• Resolve TypeScript compiler errors systematically
• Fix type mismatches and undefined behavior
• Handle null and undefined values with strict null checks
• Configure ESLint rules for TypeScript best practices
• Set up type checking in CI/CD pipeline

8. **Testing and Validation**

• Update test files to TypeScript
• Configure testing framework for TypeScript support
• Add type testing with tools like tsd or @typescript-eslint
• Validate type safety in test suites
• Set up type coverage reporting

9. **Developer Experience Enhancement**

• Configure IDE/editor for optimal TypeScript support
• Set up IntelliSense and auto-completion
• Configure debugging for TypeScript source maps
• Set up type-aware linting and formatting
• Create TypeScript-specific code snippets and templates

10. **Documentation and Team Onboarding**

• Update project documentation for TypeScript setup
• Create TypeScript coding standards and best practices guide
• Document migration decisions and type system architecture
• Set up type documentation generation
• Train team members on TypeScript development workflows
• Create troubleshooting guide for common TypeScript issues