Typescript Roadmap
20 sections • 419 topics
- 1. Type Annotations and Type Inference
- Example: Type annotations vs inference
- 2. Primitive Types (string, number, boolean, null, undefined)
- Example: Primitive type usage
- 3. Literal Types and Template Literal Types
- Example: Literal types for type safety
- 4. Array Types (T[]) and Tuple Types
- Example: Arrays and tuples
- 5. Object Types and Index Signatures
- Example: Object types and index signatures
- 6. Union Types (|) and Intersection Types (&)
- Example: Union types for flexibility
- Example: Intersection types for composition
- 7. any, unknown, never, and void Types
- any vs unknown
- void vs never
- Example: any vs unknown
- Example: never and void
- 1. Type Aliases (type) vs Interface Declarations
- Type vs Interface
- Example: Type alias
- Example: Interface
- Example: Type aliases vs interfaces
- 2. Enum Types and Const Enums
- Example: Enum types
- 3. Type Assertions (as keyword and angle-bracket syntax)
- Example: Type assertions
- 4. Type Guards and Type Narrowing Techniques
- Example: Built-in type guards
- Example: User-defined type guards
- 5. Discriminated Unions and Tagged Unions
- Example: Discriminated unions for safe state management
- 6. Mapped Types and Key Remapping
- Example: Mapped types
- 7. Conditional Types and Built-in Utility Types
- Example: Conditional types
- Key Takeaways
- 1. Generic Functions (
- Example: Generic functions
- Example: Generic methods in classes
- 2. Generic Interfaces and Generic Classes
- Example: Generic interfaces
- Example: Generic classes
- 3. Generic Constraints (extends keyword)
- Example: Generic constraints
- 4. Default Generic Parameters
- Example: Default generic parameters
- 5. Conditional Types with infer Keyword
- Example: infer keyword usage
- 6. Variance and Covariance in Generics
- Variance Rules
- Array Variance
- Example: Covariance - return types
- Example: Contravariance - parameter types
- Example: Invariance - mutable containers
- Generics Best Practices
- 1. Partial
- Example: Partial<T> for optional properties
- Example: Required<T> to enforce completeness
- 2. Pick
- Example: Pick<T, K> to select properties
- Example: Omit<T, K> to exclude properties
- 3. Record
- Example: Record<K, T> for dictionaries
- Example: keyof for type-safe property access
- 4. Exclude
- Example: Exclude<T, U> to remove types
- Example: Extract<T, U> to filter types
- 5. ReturnType
- Example: ReturnType<T> for type inference
- Example: Parameters<T> for parameter types
- 6. NonNullable
- Example: NonNullable<T> for type safety
- Example: InstanceType<T> for constructor types
- Example: Awaited<T> for Promise unwrapping
- Utility Types Reference
- Property Modifiers
- Property Selection
- Union Manipulation
- Function Types
- Class Types
- 1. Interface Declaration and Extension (extends keyword)
- Example: Basic interface declaration
- Example: Interface extension
- 2. Optional Properties (?) and readonly Modifier
- Example: Optional properties
- Example: Readonly properties
- 3. Function Types and Method Signatures in Interfaces
- Example: Method signatures
- Example: Call and construct signatures
- Example: Method overloading in interfaces
- 4. Index Signatures ([key: string]: type) for Dynamic Properties
- Example: String index signatures
- Example: Number and advanced index signatures
- 5. Interface Merging and Declaration Merging
- Example: Declaration merging
- Example: Module and global augmentation
- 6. Implementing Interfaces in Classes (implements keyword)
- Example: Basic interface implementation
- Example: Generic interface implementation
- Example: Combining inheritance and interfaces
- Interface Design Best Practices
- 1. Class Declaration and Constructor Functions
- Example: Basic class declaration
- Example: Generic classes
- 2. Property Declaration and Initialization
- Example: Property initialization patterns
- 3. Access Modifiers (public, private, protected, readonly)
- Example: Access modifiers
- Example: Protected members in inheritance
- 4. Static Members and Static Initialization Blocks
- Example: Static members
- Example: Static initialization blocks
- 5. Abstract Classes and Abstract Methods
- Example: Abstract classes
- 6. Class Inheritance (extends keyword) and super Keyword
- Example: Class inheritance
- Example: Inheritance chain
- 7. Getters (get) and Setters (set) with Type Safety
- Example: Getters and setters
- Example: Advanced accessor patterns
- 8. Parameter Properties Shorthand Syntax
- Example: Parameter properties (before/after)
- Example: Parameter properties with modifiers
- OOP Best Practices
- 1. Function Type Expressions and Call Signatures
- Example: Function type expressions
- Example: Call signatures
- 2. Function Overloading and Implementation Signatures
- Example: Function overloading
- Example: Advanced overloading patterns
- 3. Optional Parameters (?) and Default Parameter Values
- Example: Optional parameters
- Example: Default parameters
- 4. Rest Parameters (...args: T[]) and Spread Syntax
- Example: Rest parameters
- Example: Spread syntax
- 5. this Parameter and Explicit this Types
- Example: Explicit this parameter
- Example: this type utilities
- 6. Arrow Functions and Lexical this Binding
- Example: Arrow function this binding
- Example: Arrow function patterns
- Function Best Practices
- 1. Mapped Types ([K in keyof T]) and Key Remapping (as keyword)
- Example: Basic mapped types and modifiers
- Example: Key remapping with template literals
- Example: Filtering properties with conditional remapping
- 2. Template Literal Types and String Manipulation Types
- Example: Creating event name types
- Example: String manipulation utilities
- 3. Recursive Types and Recursive Conditional Types
- Example: Basic recursive types
- Example: Deep readonly and partial
- Example: Path string type for nested objects
- 4. Higher-Order Types and Type-level Programming
- Example: Type-level utilities
- Example: Tuple and array manipulation
- Example: Type-level arithmetic (simplified)
- 5. Brand Types and Nominal Typing Patterns
- Example: Basic branding with symbols
- Example: Branded primitive types
- Example: Phantom types for state machines
- 6. Type-only Imports (import type) and Exports (export type)
- Example: Type-only imports
- Example: Inline type imports (TS 4.5+)
- Example: Breaking circular dependencies
- Example: Type-only exports
- Advanced Type Manipulation Summary
- 1. typeof and instanceof Type Guards
- Example: typeof type guards
- Example: instanceof type guards
- 2. User-Defined Type Guards (is keyword)
- Example: Basic type predicates
- Example: Narrowing unknown types
- Example: Generic type guards
- 3. Assertion Functions (asserts keyword)
- Example: Basic assertion functions
- Example: Non-null assertions
- Example: Complex type assertions
- 4. Discriminated Union Type Guards
- Example: Basic discriminated unions
- Example: API response handling
- Example: Multiple discriminants
- 5. in Operator for Property Existence Checking
- Example: Basic in operator narrowing
- Example: Complex union narrowing
- Example: Combining with other guards
- 6. Control Flow Analysis and Type Narrowing
- Example: Truthiness and equality narrowing
- Example: Control flow with early returns
- Example: Assignment and control flow
- Example: Complex control flow scenarios
- Type Guards Summary
- 1. ES Module Syntax (import/export) in TypeScript
- Example: Named exports and imports
- Example: Default exports and mixed exports
- Example: Re-exports and barrel exports
- Example: Namespace imports and dynamic imports
- 2. CommonJS Interoperability (require and module.exports)
- Example: CommonJS export patterns
- Example: Importing CommonJS in TypeScript
- Example: TypeScript compiled to CommonJS
- 3. Module Resolution Strategies (Node, NodeNext, Classic)
- Example: Node resolution strategy
- Example: Node16/NodeNext resolution
- Example: Path mapping and baseUrl
- 4. Declaration Files (.d.ts) and Type Declarations
- Example: Basic declaration file
- Example: Module declaration files
- Example: Generating declaration files
- Example: @types packages
- 5. Ambient Module Declarations (declare module)
- Example: Ambient module declarations
- Example: Wildcard module declarations for assets
- Example: Module augmentation
- Example: Global augmentation from module
- 6. Triple-Slash Directives (///
- Example: Triple-slash path references (legacy)
- Example: Reference types directive
- Example: Reference lib directive
- Example: Advanced triple-slash usage
- Module System Summary
- 1. const Type Parameters and const Assertions (as const)
- Example: const type parameters
- Example: const assertions (as const)
- Example: Practical const patterns
- 2. satisfies Operator for Type Checking
- Example: satisfies vs type annotation
- Example: Practical satisfies patterns
- Example: Complex satisfies scenarios
- 3. using Declaration for Resource Management
- Example: Basic using declaration
- Example: Async disposal with await using
- Example: Practical resource management patterns
- 4. Decorator Metadata and Reflect API
- Example: Modern decorators with metadata (TS 5.0+)
- Example: Reflect Metadata API (legacy approach)
- Example: Design-time type reflection
- 5. Import Attributes and JSON Modules
- Example: JSON module imports
- Example: CSS and other module types
- Example: Typed JSON imports
- 6. Node16/NodeNext Module Resolution
- Example: Node16/NodeNext configuration
- Example: Dual package (CJS + ESM)
- Example: Subpath exports and patterns
- TypeScript 5+ Features Summary
- 1. Promise
- Example: Basic Promise types
- Example: async/await syntax
- Example: Promise combinators
- 2. Typing Async Functions and Return Types
- Example: Async function return types
- Example: Generic async functions
- Example: Async function types
- 3. Awaited
- Example: Awaited utility type
- Example: Practical Awaited usage
- Example: PromiseSettledResult types
- 4. Error Handling in Async Code (try/catch with types)
- Example: try/catch with async/await
- Example: Result type pattern
- Example: Error types and custom errors
- 5. Generator Functions (function*) and AsyncGenerator
- Example: Generator functions
- Example: Async generators
- Example: Generator type parameters
- 6. Callback Types and Event Handler Typing
- Example: Callback function types
- Example: Event handler types
- Example: Promisify callbacks
- Asynchronous Programming Summary
- 1. tsconfig.json File Structure and Options
- Example: Basic tsconfig.json Structure
- 2. Compiler Options and Strict Mode (strict: true)
- Example: Strict Mode Configuration
- 3. Path Mapping (paths) and baseUrl Configuration
- Example: Path Mapping Configuration
- 4. Include/Exclude Patterns and File Selection
- Example: File Selection Patterns
- 5. Project References and Composite Projects
- Example: Project References Setup
- 6. Build Mode (--build) and Incremental Compilation
- Example: Incremental Build Configuration
- Configuration and Compiler Options Summary
- 1. React TypeScript (React.FC, Props, useState, useEffect)
- Example: Function components with props
- Example: Event handlers and refs
- Example: Hooks with TypeScript
- 2. Vue.js TypeScript (Composition API, defineComponent, ref, computed)
- Example: Vue 3 Composition API with TypeScript
- Example: Props and emits with types
- 3. Angular TypeScript (@Component, @Injectable, Decorators)
- Example: Angular component with TypeScript
- Example: Angular service with dependency injection
- 4. Node.js TypeScript (@types/node, process, Buffer)
- Example: Node.js modules with TypeScript
- 5. Express.js TypeScript (Request, Response, NextFunction)
- Example: Express routes with TypeScript
- Example: Typed middleware
- 6. Next.js TypeScript (API Routes, getServerSideProps, getStaticProps)
- Example: Next.js pages with data fetching
- Example: Next.js API routes
- Framework Integration Summary
- 1. Jest TypeScript (ts-jest, @types/jest) Configuration
- Example: Jest configuration for TypeScript
- Example: Writing typed tests with Jest
- 2. Type-only Tests (expect-type, tsd, @ts-expect-error)
- Example: Type-only tests with expect-type
- Example: Negative type tests
- 3. Mock Typing (jest.Mock
- Example: Typed mocks with Jest
- Example: Module mocking with types
- 4. Test Coverage and Type Coverage (type-coverage) Analysis
- Example: Jest coverage configuration
- Example: Type coverage analysis
- 5. Property-Based Testing (fast-check) with TypeScript
- Example: Property-based testing with fast-check
- Example: Custom arbitraries for complex types
- 6. Contract Testing and API Type Validation (Zod, io-ts)
- Example: Zod schema validation
- Example: Contract testing with OpenAPI
- Example: MSW for API mocking
- Testing and Quality Assurance Summary
- 1. TypeScript Compilation Performance Tuning
- Example: Performance-optimized tsconfig.json
- Example: Performance diagnostics
- Example: Large project optimizations
- 2. Incremental Builds (--incremental) and Project References
- Example: Monorepo with project references
- Example: Build commands
- 3. Bundle Analysis and Tree Shaking with TypeScript
- Example: Tree-shakeable library structure
- Example: Bundle analysis with Webpack
- 4. Webpack (ts-loader, babel-loader) TypeScript Integration
- Example: Webpack with ts-loader (production)
- Example: Fast development config
- 5. Vite TypeScript and HMR (Hot Module Replacement)
- Example: Vite configuration with TypeScript
- Example: TypeScript config for Vite
- 6. esbuild and SWC Fast TypeScript Compilation
- Example: esbuild configuration
- Example: SWC configuration
- Example: Performance comparison
- Performance and Build Tools Summary
- 1. VS Code TypeScript Features and Extensions
- Example: VS Code settings for TypeScript
- Example: Useful VS Code keyboard shortcuts
- 2. ESLint TypeScript (@typescript-eslint/parser, @typescript-eslint/eslint-plugin)
- Example: ESLint configuration for TypeScript
- Example: Popular TypeScript ESLint rules
- 3. Prettier TypeScript Formatting Configuration
- Example: Prettier configuration
- Example: Format on save and pre-commit
- 4. TypeScript Language Server (tsserver) and LSP Protocol
- Example: Language server configuration
- Example: Language server plugins
- 5. Refactoring Tools and Code Actions (Quick Fix)
- Example: Common code actions
- Example: Organize imports
- 6. IntelliSense and Auto-completion in TypeScript
- Example: IntelliSense configuration
- Example: IntelliSense in action
- Development Tools and IDE Integration Summary
- 1. TypeScript Compiler Error Messages (TS2304, TS2322, TS2345)
- Example: Common compiler errors and fixes
- Example: Understanding error messages
- 2. Type Error Diagnosis and Resolution Strategies
- Example: Diagnosis techniques
- Example: Debugging type inference
- 3. Source Maps (sourceMap: true) and Debugging
- Example: Source map configuration
- Example: VS Code debugging configuration
- 4. Runtime Error Handling with Type Safety (try/catch)
- Example: Result type pattern
- Example: Custom error classes and type guards
- 5. Type-only Imports (import type) for Debugging
- Example: Type-only imports
- Example: Debugging with type imports
- 6. Conditional Compilation and Environment Types (NODE_ENV)
- Example: Environment-specific types
- Example: Feature flags and conditional types
- Error Handling and Debugging Summary
- 1. Dependency Injection (InversifyJS) and IoC Container Typing
- Example: InversifyJS dependency injection
- Example: Manual DI pattern (no framework)
- 2. Plugin Architecture and Type-safe API Design
- Example: Type-safe plugin system
- 3. Schema Validation (Zod, Yup, Joi, io-ts) TypeScript Integration
- Example: Zod schema validation
- Example: Joi validation
- 4. ORM Type Safety (Prisma, TypeORM, Drizzle, Sequelize)
- Example: Prisma type-safe ORM
- Example: TypeORM entities
- 5. GraphQL Code Generation (GraphQL Codegen) and Type Safety
- Example: GraphQL Code Generator
- 6. Microservices Communication and API Contracts (tRPC, OpenAPI)
- Example: tRPC end-to-end type safety
- Example: OpenAPI type generation
- Advanced Patterns and Enterprise Features Summary
- 1. JavaScript to TypeScript Migration Step-by-Step
- Example: Incremental migration setup
- Example: Converting a JavaScript file
- 2. Gradual Type Adoption (@ts-check, JSDoc type comments)
- Example: Using @ts-check with JSDoc
- Example: Enabling checkJs project-wide
- 3. Legacy Code Integration and Incremental Migration
- Example: Creating type stubs for legacy code
- Example: Adapter pattern for legacy data
- 4. Third-party Library Types (@types/*, DefinitelyTyped)
- Example: Working with type definitions
- 5. Team Onboarding and TypeScript Training
- Example: Onboarding checklist
- Example: Team training resources
- 6. Code Review Guidelines for TypeScript Projects
- Example: Code review checklist
- Example: PR review feedback examples
- Migration and Adoption Strategies Summary