While I applaud the initiative and effort, I want to urge the author to consult a good proofreader. I’m only in chapter 2 yet I’ve already encountered enough friction in the form of poor English to put me off. I think the substance looks great, so it’s a bit wasteful to not walk the last mile and make it genuinely enjoyable to read by eliminating blatant errors like this one:
“The Redis is an example of the server/client system.”
“The Redis is an example of the server/client system.”