Next.js · tool · fg-0303

next build fails on Next.js 16 with 'This build is using Turbopack, with a webpack config and no turbopack config'

This build is using Turbopack, with a `webpack` config and no `turbopack` config.

Verified 2026-10-15 · Confirmed by 0 builders · Trust 50/100

Cause

Next.js 16 builds with Turbopack by default and refuses to silently ignore a webpack function, since that config would not apply.

Fix

Port the webpack rules to the turbopack key, or keep webpack for builds with the --webpack flag until the plugin supports Turbopack.

Apply

// package.json
"scripts": { "build": "next build --webpack" }

Affects: Next.js 16.0 and later, any config or plugin that sets webpack

Sources

• https://nextjs.org/docs/app/guides/upgrading/version-16

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