next.js/examples/with-relay-modern/components/BlogPostPreview.js

import React from 'react'
import { createFragmentContainer, graphql } from 'react-relay'

const BlogPostPreview = props => {
  return <div key={props.post.id}>{props.post.title}</div>
}

export default createFragmentContainer(BlogPostPreview, {
  post: graphql`
    fragment BlogPostPreview_post on BlogPost {
      id
      title
    }
  `
})