Online TypeScript Guides

TypeScript adds a powerful type system to JavaScript, helping you catch errors earlier and make code easier to understand and maintain. This collection brings together resources for getting started, configuring projects, writing and typing functions, migrating existing JavaScript, and exploring advanced type-level programming. Whether you’re learning the basics or deepening your expertise, use these guides, courses, and discussions to find the next topic that fits your needs.

• TypeScript.fm is a friendly weekly podcast for TypeScript developers hosted by Kamran Ayub and Erik Onarheim. Each episode discusses TypeScript news and releases, the wider JavaScript ecosystem, tooling and real-world experience of building applications with the language, often with guests from the community. typescript.fm
• Tomasz Sułkowski on StackBlitz is the StackBlitz profile of Tomasz Sułkowski (sulco), well known for his short TypeScript and JavaScript tips. It gathers his public projects, many of them small runnable demos that illustrate a language feature or a trick, which you can open and edit directly in the browser. sulco.stackblitz.io
• Type-Level TypeScript is an online course by Gabriel Vergnaud to become a TypeScript expert. It explores the most advanced features of the type system, from objects, records, arrays and tuples to conditional types, recursive types, template literal types, union types, mapped types, assignability and the design of type-safe APIs, and each chapter ends with fun interactive challenges solved directly in the browser. The first chapters are free. type-level-typescript.com
• The TSConfig Cheat Sheet by Matt Pocock from Total TypeScript explains the essential tsconfig.json options and gives a concise, ready-to-copy configuration for your projects. It covers the base options, strictness, whether you transpile with tsc or another tool, and whether your code runs in the DOM or not. The same settings are also published as an npm package you can extend. totaltypescript.com
• Strategies for migrating to TypeScript by Axel Rauschmayer describes three strategies to migrate a JavaScript project: mixing JavaScript and TypeScript files with the allowJs option, keeping JavaScript and adding type information with JSDoc comments and type definition files, and using snapshot tests of the compiler errors to migrate large projects step by step. The 2ality blog is temporarily offline at the time of writing. 2ality.com
• TypeScript Function Syntaxes by Kent C. Dodds is a handy reference of the syntax for the various kinds of functions and function types in TypeScript: function declarations and expressions, optional and default parameters, rest parameters, object methods, classes, modules, overloads, generators, async functions, generics, type guards and assertion functions, each with a simple example. kentcdodds.com
• TypeScript Basics - A Definitive Guide by Ganesh Mani on DEV Community is an introduction for JavaScript developers who want to start with TypeScript. It explains what TypeScript is and why you need it, how to set it up, then walks through basic static types, type inference, interfaces and generics with short examples. dev.to