nuxt.config.js

build: {
    extractCSS: false,
    extend (config, {isDev}) {
      if (isDev && process.client) {
        config.module.rules.push({
          enforce: 'pre',
          test: /\.(js|vue)$/,
          loader: 'eslint-loader',
          exclude: /(node_modules)/
        })
      }
    }
  }