Fix: Failed to resolve entry for package.json error

The ‘Failed to resolve entry for package.json’ error occurs when JavaScript bundlers like Vite, Rollup, or similar tools cannot find the correct entry point in a package’s package.json file, typically due to missing or incorrect main/module/exports fields.

How the Error Happens

❌ Error Scenario:

// ❌ This causes the error when bundling
import something from 'problematic-package';
// Error: Failed to resolve entry for package.json

✅ Quick Fix - Resolve Package Entry Points

Solution 1: Check Package.json Entry Fields

// ✅ Ensure package.json has proper entry fields
{
  "name": "my-package",
  "main": "dist/index.js",        // ✅ CommonJS entry
  "module": "dist/index.esm.js",  // ✅ ES Module entry
  "browser": "dist/index.browser.js", // ✅ Browser entry
  "exports": {
    ".": {
      "import": "./dist/index.esm.js",
      "require": "./dist/index.js"
    }
  }
}

Solution 2: Use Specific File Extensions

// ❌ Import without extension may fail
import { something } from 'package';

// ✅ Import with specific file extension
import { something } from 'package/dist/index.js';

Solution 3: Configure Bundler Resolution

// ✅ For Vite (vite.config.js)
export default {
  resolve: {
    extensions: ['.js', '.ts', '.jsx', '.tsx', '.json'],
    mainFields: ['module', 'jsnext:main', 'browser', 'main'] // ✅ Order matters
  }
}

// ✅ For Rollup (rollup.config.js)
import { nodeResolve } from '@rollup/plugin-node-resolve';

export default {
  plugins: [
    nodeResolve({
      mainFields: ['module', 'main'], // ✅ Specify resolution order
      extensions: ['.js', '.ts']
    })
  ]
};

Solution 4: Install Missing Package

# ✅ Ensure package is properly installed
npm install problematic-package

# ✅ Clear cache if needed
npm cache clean --force
rm -rf node_modules package-lock.json
npm install