getInitialProps.tsx

const getInitialProps = async () => {
  const subreddit = 'typescript'
  const response = await fetch(`https://www.reddit.com/r/${subreddit}.json`)
  const result = await response.json() as RedditResult

  return {
    subreddit,
    posts: result.data.children
  }
}

Posts.getInitialProps = getInitialProps