Publishing a package is pretty straightforward and not time-consuming. Moreover, it's an excellent option to make your code reusable and available for many of your projects.

First, you have to create an account on npmjs website.

Before we start doing all the necessary for publishing the package, it's better to prepare your repository in advance. I'll create a repository on GitHub. Create repository with name math-library-add.

Here is how looks my repository configuration.

Let's clone it and go inside the folder:

git clone https://github.com/obaranovskyi/math-library-add && cd math-library-add

Add .gitignore file, not to publish the node_modules.
In our case, it looks pretty simple:

node_modules

Init npm inside of the project:

npm init --yes

You accept all defaults when you're using --yes flag.

Install typescript package to dev-dependencies

npm install -D typescript

Init typescript:

npx tsc --init

This command creates the default tsconfig.json file. Now we need to configure it.

1. We need to uncomment declaration, declarationMap, and sourceMap.
2. Include src folder, by adding include property with value ["src"]
3. Add outDir with the name of the folder where we want to keep our compiled javascript files. I'll name my folder library.

Your configuration should like this:

{
  "compilerOptions": {
    "target": "es2016",
    "module": "commonjs",
    "declaration": true,
    "declarationMap": true,
    "sourceMap": true,
    "esModuleInterop": true,
    "forceConsistentCasingInFileNames": true,
    "strict": true,
    "skipLibCheck": true,
    "outDir": "library"
  },
  "include": [
    "src" 
  ],
}

Let's add the code we want to publish and reuse later on.

Create folder src with the file index.ts.
I'll put something simple inside.

export function add(x: number, y: number): number {
  return x + y;
}

• Update your package.json file:
  • We need to update main property to library/index.ts. So others can determine the main file in the project.
  • types has to be set to library. Here we're pointing to the folder where we keep the types.
  • To scripts we need to add build script, it looks like this tsc -p .
  • Update keywords. In my case, I'll add math, add, library, typescript.
  • Update author, put your name there.
  • Add repository with value { "type": "git", "url": "https://github.com/obaranovskyi/math-library-add.git" },
  • Add some description.
  • In addition, you can update the license. We can use MIT.

Your package.json file has to look kind of like this:

{
  "name": "math-library-add",
  "version": "1.0.0",
  "description": "",
  "main": "library/index.ts",
  "types": "library",
  "scripts": {
    "build": "tsc -p ."
  },
  "keywords": [
    "math",
    "add",
    "library",
    "typescript"
  ],
  "author": "Oleh Baranovskyi",
  "license": "MIT",
  "repository": {
      "type": "git",
      "url": "https://github.com/obaranovskyi/math-library-add.git"
  },
  "description": "This is just a test library.",
  "devDependencies": {
    "typescript": "^5.0.4"
  }
}

First, we need to build the project.

npm run build

The project was compiled into library folder.

We're ready to publish our package:

npm publish --access public

Now the we need to commit and push our changes to GitHub.

git add .
git commit -a -m "Library base."
git push