...
"production": {
      "plugins": [
        ["transform-replace-object-assign", "simple-assign"],
        "transform-dev-warning", "transform-decorators-legacy", "transform-es2015-arrow-functions",
        [
          "css-modules-transform", {
            "extensions": [".css", ".scss"],
            "extractCss": "./lib/css/assets.css",
            "generateScopedName": "[name]__[local]___[hash:base64:5]",
            "preprocessCss": "./babel/preprocess-function.js"
          }
        ]
      ]
    },
...