How to create a sitemap for a Gatsby site

Install the Gatsby plugin:

npm install gatsby-plugin-sitemap

Then, add the root URL of your site (before the part that starts with /) to your gatsby-config.js, and activate the plugin:

// gatsby-config.js

module.exports = {
  siteMetadata: {
    siteUrl: "https://benborgers.com"
  },
  plugins: [
    "gatsby-plugin-sitemap"
  ]
}

Done! Your sitemap will be created at /sitemap.xml in production builds of your Gatsby website, and will also be properly linked in the <head> of each page.