I've done a few of these for people at home (albeit not quite so complex) and for myself. I built the application/infrastructure monitoring systems where I work as well. As one poster said above, document everything, even the commands. It works, although it is tedious. But there is a certain joy using something you created, even if it is something of a "labor of love" to maintain it.

I want to get out of IT after 20 years, but there is no way I will stop tinkering with OSs, Raspberry Pi IoT devices, SoC, light coding, etc. It's different when it's a hobby than when you're faced with time constraints, budgets, and nagging bosses.

A project I'm about to start at home is taking an existing 1080P dash cam (front and rear) that features great night vision and hack it using a Raspberry Pi that handles motion detection, sends stills, and uploads to the cloud. Sure, I could go buy an extant system that just works, but what's the fun in that? It's like Legos. I could go buy my kid a fully-assembled car or spaceship, but I'd rather him learn how to follow instructions, see cause and effect, and experience the pride of a job well done. YMMV. There is something really uplifting in seeing "complex" technical stuff working that you yourself built. It doesn't even have to be as good as existing tech.