Kitchenaid direct-drive stand mixer. I have one from the 1950s that has been used multiple times a week since it was bought new by my grandmother.
The dough hook, whisk, and other attachments secure in place with machined fittings so there is no play or wiggle. This has made them last.
I took the top off of it 10 years ago to make sure it was still properly lubricated. That’s all the maintenance it has ever had. (Well I broke one of the Pyrex mixing bowls…but eBay)
For example the first recipe will not work as expected with out a multi-column unique index (specifically the MySql example).
I feel that the preexisting knowledge required for such examples does not align with the stated target audience for the book.