[1646] Can not access env variables on server side

// nuxt.config.js
build: {
  env: {
    VERSION: '1.0.0'
  }
}

// server/index.js
console.log(process.env.VERSION) // undefined

I can get the env variables in components, but i can't get env variables in server side code. I have try to resolve it with some transform plugins(like: babel-plugin-transform-define), because I'm using babel, but still not work.