From 15,000 database connections to under 100: DigitalOcean's tech debt tale
blog.digitalocean.com
blog.digitalocean.com
It was very clear that the people writing the tutorials actually used what they taught in production environments.
This is a stark contrast to "modern" documentation for Google Cloud or similar services where the people writing the documentation didn't actually have to backup what they were teaching with actual experience (because at their company they used proprietary technologies that involved copying and pasting from other proprietary technologies).
Of course they weren't all perfect but I put it up there as some of the better documentation I've ever worked with (perhaps made possible in the 1-off format where their scope was relatively limited and not trying to upsell an auxiliary service).
Big shoutout to Digital Ocean for being a reliable source for tutorials and hosting!