A snippet with instructions how to deploy an ACT website to GitHub Pages using a gh-pages package

# add a gh-pages package
npm install gh-pages --save-dev

For GitHub Organization or User pages (repository username.github.io), a simple deploy script should be added to package.json

// package.json
    {
        "scripts": {
            ...
            "deploy": "gatsby build && gh-pages -d public -b master",
        }
    }

For repository pages (URLs of the form https://username.github.io/reponame/), an additional prefix should be added as well.

// package.json
    {
        "scripts": {
            ...
            "deploy": "gatsby build --prefix-paths && gh-pages -d public -b master",
        }
    }

// gatsby-config.js
module.exports = {
    pathPrefix: "/reponame",
}