[1280] [nuxt] store/index.js should export a method which returns a Vuex instance.

Im configuring Vuex Classic according to the documentation and am returning the following error.

Nuxt.js Error:
   
   Error: [nuxt] store/index.js should export a method which returns a Vuex instance.
       at getModule (.nuxt/store.js:58:10)
       at Object.module.exports.map../index.js (.nuxt/store.js:21:14)
       at __webpack_require__ (webpack:/webpack/bootstrap a643748ba1b66033c6f3:25:0)
       at Object.<anonymous> (server-bundle.js:1570:69)
       at __webpack_require__ (webpack:/webpack/bootstrap a643748ba1b66033c6f3:25:0)
       at Object.<anonymous> (server-bundle.js:1057:65)
       at __webpack_require__ (webpack:/webpack/bootstrap a643748ba1b66033c6f3:25:0)
       at server-bundle.js:92:18
       at Object.<anonymous> (server-bundle.js:95:10)
       at evaluateModule (/home/daniel/dev/kino/site/node_modules/vue-server-renderer/build.js:7747:21)
       at /home/daniel/dev/kino/site/node_modules/vue-server-renderer/build.js:7805:18
       at Promise (<anonymous>)
       at /home/daniel/dev/kino/site/node_modules/vue-server-renderer/build.js:7797:14
       at Object.renderToString (/home/daniel/dev/kino/site/node_modules/vue-server-renderer/build.js:7951:9)
       at P (/home/daniel/dev/kino/site/node_modules/nuxt/node_modules/pify/index.js:49:6)
       at Promise (<anonymous>)

Other error random:

Nuxt.js Error:

Error: [vuex] must call Vue.use(Vuex) before creating a store instance.
    at assert (/home/daniel/dev/kino/site/node_modules/vuex/dist/vuex.js:102:27)
    at new Store (/home/daniel/dev/kino/site/node_modules/vuex/dist/vuex.js:249:3)
    at Object.<anonymous> (store/index.js:3:14)
    at __webpack_require__ (webpack:/webpack/bootstrap a643748ba1b66033c6f3:25:0)
    at Object.<anonymous> (server-bundle.js:1506:65)
    at __webpack_require__ (webpack:/webpack/bootstrap a643748ba1b66033c6f3:25:0)
    at webpackContext (webpack:/middleware nonrecursive ^\.\/.*\.(js|ts)$:5:0)
    at getModule (.nuxt/middleware.js:6:13)
    at Object.<anonymous> (.nuxt/middleware.js:16:21)
    at __webpack_require__ (webpack:/webpack/bootstrap a643748ba1b66033c6f3:25:0)
    at Object.<anonymous> (server-bundle.js:1056:70)
    at __webpack_require__ (webpack:/webpack/bootstrap a643748ba1b66033c6f3:25:0)
    at server-bundle.js:92:18
    at Object.<anonymous> (server-bundle.js:95:10)
    at evaluateModule (/home/daniel/dev/kino/site/node_modules/vue-server-renderer/build.js:7747:21)
    at /home/daniel/dev/kino/site/node_modules/vue-server-renderer/build.js:7805:18

store/index.js

import Vuex from 'vuex'

const store = new Vuex.Store({
  state: {
    counter: 0
  },
  mutations: {
    increment (state) {
      state.counter++
    }
  }
})

export default store

From what I understood in the documentation nuxt would take care of me.