Feedback wanted on book ideas

Hi all, I'm a software engineer of over 20 years and I love sharing my knowledge with other developers. I've run several user groups over the years and been blogging for quite a while (and lost a few of those blogs over the years). I've been contemplating doing some deeper work but I'm having trouble picking which area to focus on that would be the most valuable to people and I was hoping I might be able to get some feedback from this community. I'll include each one as a comment below, feel free to like it, comment etc on whichever one(s) you think you would personally find value in. If this kind of post isn't allowed feel free to delete.

Thank you in advance, I really do appreciate it!

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