Type-safe JavaScript with TypeScript
TypeScript types disappear at runtime, and the most common mistakes happen when developers forget this. Learn the pitfalls of typeof, instanceof, type assertions, and structural checking so you stop trusting types at runtime.
Install Prettier to format TypeScript code automatically. Set up editor integration, CI checks, and make Prettier work alongside ESLint without conflicts.
Compare tsx and ts-node for running TypeScript directly in Node.js. Understand speed, ESM support, watch mode, and which tool fits your workflow.
Set up Vitest to test TypeScript code with zero configuration. Write unit tests, run them in watch mode, and use built-in type testing to catch type-level bugs.
Use Vitest's expectTypeOf and assertType to test TypeScript types at compile time. Catch type-level regressions before they reach production.
Set up VS Code to debug TypeScript with breakpoints, source maps, and step-through debugging. Configure launch.json for Node.js and browser debugging.
Organize your TypeScript workflow with npm scripts for building, type checking, linting, testing, and running dev servers from a single package.json.
Cut TypeScript compile times with incremental builds, project references, skipLibCheck, and smart tool choices. Get faster feedback without sacrificing type safety.
Avoid the most frequent TypeScript tooling mistakes: missing source maps for debugging, slow CI builds, conflicting ESLint and Prettier configs, and running tsc when you should use tsx.
Learn how to design domain models in TypeScript that reflect real-world concepts, enforce valid states, and keep business logic clear and type-safe.
Learn how to organize business logic into typed service layers that keep your TypeScript codebase maintainable, testable, and free of scattered domain rules.
Learn how to set clear package boundaries in TypeScript projects using folder conventions, ESLint rules, and dependency direction to keep a large codebase maintainable.
