Introduction

This post will help you to publish your own react library to npm, so you can reuse your own component and functions.

This post is intended for people who just want to follow the steps without understand the details.

Before start, You will need to have NPM, Typescript and other common dev dependencies installed

Steps

First, create tsconfig.json file at your project root:

{
  "compilerOptions": {
    "target": "es5",
    "lib": [
      "dom",
      "dom.iterable",
      "esnext"
    ],
    "allowJs": true,
    "declaration": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "strict": true,
    "forceConsistentCasingInFileNames": true,
    "noFallthroughCasesInSwitch": true,
    "module": "esnext",
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "isolatedModules": true,
    "jsx": "react",
    "outDir": "lib/esm",
  },
  "include": [
    "src"
  ],
  "exclude": ["node_modules", "lib"]
}

then run npm init, and modify package.json flie:

...
  "main": "./lib/cjs/index.js",
  "module": "./lib/esm/index.js",
  "types": "./lib/esm/index.d.ts",
  "files": [
    "src"
  ],
  "scripts": {
    "build": "npm run build:esm && npm run build:cjs",
    "build:esm": "tsc",
    "build:cjs": "tsc --module commonjs --outDir lib/cjs",
    "publish": "npm publish"
  },
...
  "peerDependencies": {
    "react": "^17.0.2",
    "react-dom": "^17.0.2"
  },
  "devDependencies": {
    "@types/node": "16.11.10",
    "@types/react": "^17.0.37"
  },
  "dependencies": {
    "@types/react-dom": "^17.0.11"
  }
...
}

Add .gitignore file if you are using git:

# dependencies
/node_modules

Create src folder and src/index.tsx file:

import React from "react";

export function CheckLib(){
    return <div>Lib Ok</div>
}

Then run npm run build to create the build folder.

Run npm publish to publish your package.

Finally, you can use npm install <your-package-name> to install your library in other project.

You may need to run npm login to login your npm account if you never logged in before.

Run Local Version of Library

If you want to have a playground of your library or just want to use it.

Run npm link at your library root.
In your other project root run npm link "You-Library-Name-Here".
After this, you should be able to find your library inside the node_modules folder.

Notice

I tested this method with a project created by create-next-app. I assume this will work CRA as well.
If you find your project does not run your library, you may need to explore some more complex methods.
I'm using Windows for this method, if you're using Mac or other OS you may want to change build script to work with your CLI environment.

Thanks