How to fix common Netlify build errors

Build failures are one of the most frustrating parts of deploying a site. Everything works locally, you push to GitHub, Netlify starts building… and then it fails.

The good news is that most Netlify build errors fall into a small number of common categories. Once you know what to look for, fixing them becomes much easier.

In this guide, we’ll walk through how Netlify builds your site, how to read build logs effectively, and how to fix the most common errors you’ll encounter.

How Netlify builds your site

Every Netlify deploy follows roughly the same process:

1. Netlify clones your Git repository
2. It installs dependencies
3. It runs your build command
4. It publishes the output directory

If anything fails in steps 2 or 3, the deploy fails.

Understanding which step failed is the key to debugging.

Start with the build log

When a build fails, click the failed deploy in the Netlify dashboard and open the Deploy log.

Don’t scroll randomly. Start from the top and work down until you see:

• A red error message
• A stack trace
• A command that exited with a non-zero status

That section usually tells you exactly what went wrong.

Common Netlify build errors and how to fix them

Dependency install failures

Symptoms:

• Errors mentioning npm install, yarn install, or pnpm install
• Messages like Cannot find module or ERESOLVE

Common causes:

• Lockfile and package manager mismatch
• Corrupted or outdated lockfiles
• Missing dependencies

Fixes:

• Make sure you commit the correct lockfile (package-lock.json, yarn.lock, or pnpm-lock.yaml)
• Use only one package manager
• Delete node_modules, reinstall locally, and commit updated lockfiles

Wrong Node.js version

Symptoms:

• Errors like SyntaxError: Unexpected token
• Warnings about unsupported Node versions

Fixes:

Specify the Node version explicitly.

Create or update netlify.toml:

[build]
  node_version = "18"

Or add an .nvmrc file:

18

Netlify will respect both.

Build command works locally but fails on Netlify

Symptoms:

• Works on your machine
• Fails in CI

Common causes:

• Missing environment variables
• Case-sensitive file paths
• OS differences (macOS vs Linux)

Fixes:

• Double-check environment variables in the Netlify dashboard
• Ensure import paths match exact casing
• Avoid relying on globally installed tools

Missing environment variables

Symptoms:

• Errors related to API keys
• Build crashes during data fetching

Fixes:

Add required variables in Site settings → Environment variables.

If you need different values per context:

• Production
• Deploy previews
• Branch deploys

Configure them separately to avoid surprises.

Wrong publish directory

Symptoms:

• Build succeeds but site shows a 404
• Message like “Deploy directory does not exist”

Fixes:

Verify your build output directory.

Examples:

• Next.js: .next
• Gatsby: public
• Astro: dist
• Vite: dist

Update netlify.toml if needed:

[build]
  command = "npm run build"
  publish = "dist"

Monorepo path issues

Symptoms:

• Netlify can’t find package.json
• Build runs in the wrong directory

Fixes:

Set a base directory:

[build]
  base = "apps/web"
  command = "npm run build"
  publish = "dist"

Framework adapter issues

Symptoms:

• Next.js or Astro builds fail unexpectedly
• Errors referencing adapters

Fixes:

• Make sure you’re using the official Netlify adapter
• Check framework docs for Netlify-specific configuration
• Keep adapters up to date

Reproducing the build locally

Use the Netlify CLI to run the build exactly like Netlify does:

npm install -g netlify-cli
netlify build

This often surfaces issues you don’t see with npm run build alone.

When all else fails

If you’re stuck:

• Compare a successful older deploy to the failing one
• Check recent dependency upgrades
• Search the exact error message (Netlify errors are very searchable)
• Ask in the Netlify community forum

Final thoughts

Netlify build errors can feel intimidating, but they’re usually straightforward once you know where to look. Treat the build log as your primary debugging tool, and fix one issue at a time.

Once you get comfortable reading logs, failed builds become a minor speed bump instead of a blocker.