I use GitHub pages with no build step (GitHub handles that). I use my repos root folder for my page content, starting with index.md. I have a custom domain and just point the a record or cname at my GitHub address or IP. Works great for me and I haven’t noticed a lot of downtime, but I don’t really monitor either.

Edit: It is a little slow to build when you make changes. My changes take a minute or two to appear on the site.