{
  // Keep main and _app chunks unsplitted in webpack 5
  // as we don't need a separate vendor chunk from that
  // and all other chunk depend on them so there is no
  // duplication that need to be pulled out.
  chunks: (chunk) =>
    !/^(polyfills|main|pages\/_app)$/.test(chunk.name) &&
    !MIDDLEWARE_ROUTE.test(chunk.name),
  cacheGroups: {
    framework: {
      chunks: (chunk: webpack.compilation.Chunk) =>
        !chunk.name?.match(MIDDLEWARE_ROUTE),
      name: 'framework',
      test(module) {
        const resource =
          module.nameForCondition && module.nameForCondition()
        if (!resource) {
          return false
        }
        return topLevelFrameworkPaths.some((packagePath) =>
          resource.startsWith(packagePath)
        )
      },
      priority: 40,
      // Don't let webpack eliminate this chunk (prevents this chunk from
      // becoming a part of the commons chunk)
      enforce: true,
    },
    lib: {
      test(module: {
        size: Function
        nameForCondition: Function
      }): boolean {
        return (
          module.size() > 160000 &&
          /node_modules[/\\]/.test(module.nameForCondition() || '')
        )
      },
      name(module: {
        type: string
        libIdent?: Function
        updateHash: (hash: crypto.Hash) => void
      }): string {
        const hash = crypto.createHash('sha1')
        if (isModuleCSS(module)) {
          module.updateHash(hash)
        } else {
          if (!module.libIdent) {
            throw new Error(
              `Encountered unknown module type: ${module.type}. Please open an issue.`
            )
          }
 
          hash.update(module.libIdent({ context: dir }))
        }
 
        return hash.digest('hex').substring(0, 8)
      },
      priority: 30,
      minChunks: 1,
      reuseExistingChunk: true,
    },
    commons: {
      name: 'commons',
      minChunks: totalPages,
      priority: 20,
    },
    middleware: {
      chunks: (chunk: webpack.compilation.Chunk) =>
        chunk.name?.match(MIDDLEWARE_ROUTE),
      filename: 'server/middleware-chunks/[name].js',
      minChunks: 2,
      enforce: true,
    },
  },
  maxInitialRequests: 25,
  minSize: 20000,
}