Next.js Bundle Analyzer Error Fix

In this tutorial, you'll learn about Next.js Bundle Analyzer Error Fix. We cover key concepts, practical examples, and best practices.

The Problem

Error: Module not found: Can't resolve '@next/bundle-analyzer'

The bundle analyzer package is not installed. It must be a dev dependency.

Wrong

// next.config.js
const withBundleAnalyzer = require('@next/bundle-analyzer')({
  enabled: true,
})

module.exports = withBundleAnalyzer({})

Output: Error: Module not found: Can't resolve '@next/bundle-analyzer' when building.

Right

Install the package:

npm install --save-dev @next/bundle-analyzer

Configure conditionally:

// next.config.js
const withBundleAnalyzer = require('@next/bundle-analyzer')({
  enabled: process.env.ANALYZE === 'true',
})

module.exports = withBundleAnalyzer({
  // your Next.js config
})

Run the analysis:

ANALYZE=true npm run build

Expected output: two HTML files open in the browser showing client and server bundle visualizations.

Prevention

• Install @next/bundle-analyzer as a dev dependency
• Enable the analyzer conditionally with an environment variable
• Analyze bundles before every major deployment

Common Mistakes with bundle analyzer

1. Mixing let bindings with <- bindings in do notation, producing type errors
2. Overlapping type class instances that cause GHC to reject the program with ambiguous dispatch errors
3. Non-exhaustive pattern matches that compile with warnings then crash at runtime

These mistakes appear frequently in real-world NEXTJS code. DodaTech's contributors have identified these patterns through analysis of open-source projects and production systems.

Practice Exercise

Write a pure function that safely divides two integers using Maybe, then test it with edge cases like division by zero and negative numbers.

This exercise reinforces the concepts covered in this guide. Try implementing it before checking online solutions.

FAQ