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Build

By the end of this step, you'll have a simple working program in Node!

Assignment

From the root of your repository, run npm init -y to create a new Node.js project.
Add TypeScript along with types for node, and tsx (TypeScript Execute) which will allow you to run TypeScript files directly in Node.js:

npm install -D typescript @types/node tsx

The -D flag installs the packages as development dependencies, which means they won't be included in your production build.

Configure TypeScript by creating a tsconfig.json file in the root of your project:

{
  "compilerOptions": {
    "baseUrl": ".",
    "target": "esnext",
    "module": "esnext",
    "rootDir": "./src",
    "outDir": "./dist",
    "strict": true,
    "moduleResolution": "Node",
    "esModuleInterop": true,
    "skipLibCheck": true
  },
  "include": ["./src/**/*.ts"],
  "exclude": ["node_modules"]
}

include specifies the files to include in the compilation
exclude specifies the files to exclude from the compilation
strict enables all strict type checking options
esModuleInterop allows you to use ES module syntax
moduleResolution specifies how modules are resolved
baseURL specifies the base directory for module resolution

Configure the package.json in the root of your project:
- add "type":"module". This means we can use the ES module syntax in our project for imports and exports.
- add a start script that runs tsx ./src/index.ts - this will run the CLI.

{
...
  "type": "module",
  "scripts": {
    "start": "tsx ./src/index.ts"
  },
...
}

Create a src directory - this is where your project's TypeScript code will live.
In src/index.ts, create a main() function:

function main() {
  console.log("Hello, world!");
}

main();

To pass off this step, from the root of your project, run:

npm run start

If you see "Hello, world!" printed in the console, you're good to go!

Submit the CLI tests.