Setting Up TypeScript in Your Project

Installing TypeScript

To use TypeScript, install it as a dev dependency in your project:

npm install typescript --save-dev

Or install globally:

npm install -g typescript

Then confirm it’s installed:

tsc --version

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Creating a tsconfig.json File

Run the following command to generate a base config:

npx tsc --init

This creates a tsconfig.json file which controls how TypeScript compiles your code.

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Basic Compiler Options

Here’s a minimal tsconfig.json for most projects:

{
  "compilerOptions": {
    "target": "ES2020",
    "module": "ESNext",
    "outDir": "dist",
    "rootDir": "src",
    "strict": true,
    "esModuleInterop": true
  },
  "include": ["src"]
}

Option	Purpose
strict	Enables all type-checking rules
esModuleInterop	Allows import x from 'y' style imports
rootDir/outDir	Control where your source and compiled files live

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Compiling TypeScript to JavaScript

Place your .ts files in a src/ folder, then run:

npx tsc

This compiles .ts files into .js in the dist/ folder (or wherever you configured).

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Working with TypeScript in Node.js

Add this to package.json:

"scripts": {
  "build": "tsc",
  "start": "node dist/index.js"
}

Use ts-node for quicker development:

npm install ts-node --save-dev

Run a file:

npx ts-node src/index.ts

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Summary

• Install TypeScript via npm
• Generate a tsconfig.json to control compilation
• Use tsc or ts-node to compile/run code
• Setup proper src and dist folders for clean separation

Next up: basic types and how to annotate your variables like a pro.