next.js/examples/with-redux/pages/_app.js

import App, {Container} from 'next/app'
import React from 'react'
import withReduxStore from '../lib/with-redux-store'
import { Provider } from 'react-redux'

class MyApp extends App {
  render () {
    const {Component, pageProps, reduxStore} = this.props
    return <Container>
      <Provider store={reduxStore}>
        <Component {...pageProps} />
      </Provider>
    </Container>
  }
}

export default withReduxStore(MyApp)