Writing a book on server deployment for makers and need advice about scope

Hello you all!

I finally quit my job and will be making things again (last time was back in high school), so very exited and all. One of the first things I want to do is to write an introductory book to server deployment for makers and others.

I believe having a cheap VPS is good option for side projects and aspiring businesses and also believe that people should be learning about fundamentals before doing their complicated containers or serverless setups.

I want my book to be very practical and hands on (most likely combining enough theory and practice) and this is a place I struggle a little. I wish to have a general book for anyone, but server deployment can be a wide topic simply because they are many tech stacks.

My current approach is to write in general, but have one final example with deploying a Ruby on Rails & PostgreSQL application. Do you think that's a good approach? 90% of things would be generally applicable content, people would not have to know Ruby to follow up.

Other options:

1, Keep writing in general, but include at least one more stack next to Rails. Maybe Python (or suggest).

2, Change the book not to be so general and rather be directly targeted to Rails developers. Perhaps doing "other" stack as a separate edition of the book later.

What do you think?