manual.txt

Check for broken links:
  yarn run check-external-links

  It takes a while and is a bit messy. Here are some known weird responses:
    403 (quora) - often indicates false-positive, server doesn't like a robot doing a HEAD request
    405 (amazon) - often indicates false-positive, server doesn't support HEAD

  Note: Due to the meta tags on each page, you'll get broken links on this run until you've published all pages to production.

Validate meta tags
  Meta tags for articles are well-formed
  Meta tags for front page and other non-articles are well-formed
  Test with structured data validators:
    https://developers.facebook.com/tools/debug/
    https://cards-dev.twitter.com/validator
    https://search.google.com/test/rich-results

Validate rss/atom
  test using feedly.com (other RSS tools?)
  validator: https://validator.w3.org/feed/
  Filed bug for key validation failure on RSS: https://github.com/jpmonette/feed/issues/41

Vercel configuration
  Caching
  Trailing slash
  Redirects