How to fix Cannot find name 'process'. Do you need to install type definitions for node? Try `npm i @types/node`. in TypeScript

Open your terminal and install the official Node.js type definitions package. This provides TypeScript with all the type information needed to recognize Node.js globals.

npm install --save-dev @types/node

If you are using Yarn:

yarn add --dev @types/node

If you are using pnpm:

pnpm add --save-dev @types/node

Open your tsconfig.json file and ensure it includes "node" in the types array. If you don't have a types array, add one.

{
  "compilerOptions": {
    "lib": ["es2015", "dom"],
    "types": ["node"]
  }
}

Alternatively, if you want to be more explicit about which types to include, you can reference @types/node directly:

{
  "compilerOptions": {
    "types": ["node", "jest"]
  }
}

If you omit the "types" array entirely, TypeScript will include all @types packages found in node_modules, which works for most projects.

Your IDE may be caching the old TypeScript compilation results. Restart the TypeScript language server to pick up the new type definitions.

For VS Code:
- Open the Command Palette (Ctrl+Shift+P or Cmd+Shift+P)
- Search for "TypeScript: Restart TS Server"
- Press Enter

Alternatively, reload the entire window:
- Open the Command Palette
- Search for "Developer: Reload Window"
- Press Enter

For WebStorm/IntelliJ:
- Go to File > Invalidate Caches / Restart
- Choose "Invalidate and Restart"

After installing @types/node and restarting your IDE, you should be able to use Node.js globals without errors. Test by accessing the process object:

// Now this works without TypeScript errors
console.log(process.env.NODE_ENV);
console.log(process.cwd());
console.log(process.version);

// You can also use other Node.js globals
const filepath = require("path").join(__dirname, "file.txt");

If you still see errors, verify that @types/node was installed correctly by checking node_modules/@types/node exists.

If you have both Node.js server code and browser/frontend code in the same project, you may need separate tsconfig files. Create a tsconfig.node.json for server-side code:

{
  "extends": "./tsconfig.json",
  "compilerOptions": {
    "module": "commonjs",
    "lib": ["es2015"],
    "types": ["node"]
  },
  "include": ["server/**/*"],
  "exclude": ["node_modules", "dist"]
}

Then reference it in your build tool configuration (for example, in tsup, esbuild, or webpack) when compiling server-side code. Keep your main tsconfig.json without Node.js types for frontend code to avoid bundling unnecessary type definitions.

Create React App intentionally excludes @types/node from browser code because process is not available in the browser. If you need to access environment variables in a Create React App project, use the REACT_APP_ prefix:

// Correct for Create React App
const apiKey = process.env.REACT_APP_API_KEY;

// Define in .env file
// REACT_APP_API_KEY=your_key_here

If you need process in backend code that runs outside Create React App (like a server file or build script), keep that code in a separate folder and use a separate tsconfig.node.json with @types/node included.