Just my opinion but it sounds like you're making a lot of additional manual work for yourself with little to no benefit.
I could understand if you were able to maybe monetise the contact information you collect but as you said you delete everything once you validate it seems you are validating just for the sake of validating?
For example how would you deal with someone out of work due to COVID and wanting to use this time to retrain and get into the software engineer field? I can't imagine they would care about (or even know about) having a LinkedIn profile with zero related employment, no contacts to network with, etc.
I know I am being a little 'difficult' with my question and I am not criticising I am just interested on your thought process more than anything.
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Update: Just realised you edited your original reply so my reply doesn't make quite as much sense now :)
I think your direct email option is good. If it were me I would automate the direct email with a little bit of weak validation such as "please explain in one or two sentences your situation" then anyone who emails with a few words are automatically validated and any blank or one word emails are either auto-deleted or put aside for manual validation.
Just an idea though. I figure posting to HN means you wanted a little feedback :)
Best of luck with your book. I don't have a need for it right now (thankfully) but I hope it helps others as it appears you have a put a lot of thought and work into it.
I love the auto-replying-to-the-email suggestion. I didn't think of this: I might do this next time!
My goal with the form was to have people explicitly confirm details (like their role and employment status). Beforehand, I got a few requests for free copies from non-developers, and some people outside tech. This book is not really helpful for them, and I wanted to reduce this kind of support burden, by adding an automated message with the form (you can see it in action).
But finally, let me admit that I was just excited to build (what I thought was) a sensible dynamic form, automate storing the data in DynamoDB, then deleting it when the validation script runs, running the backend on Lambda that I played with for the first time. Trying out new tools: any opportunity is a good opportunity!
I could understand if you were able to maybe monetise the contact information you collect but as you said you delete everything once you validate it seems you are validating just for the sake of validating?
For example how would you deal with someone out of work due to COVID and wanting to use this time to retrain and get into the software engineer field? I can't imagine they would care about (or even know about) having a LinkedIn profile with zero related employment, no contacts to network with, etc.
I know I am being a little 'difficult' with my question and I am not criticising I am just interested on your thought process more than anything.
-----
Update: Just realised you edited your original reply so my reply doesn't make quite as much sense now :)
I think your direct email option is good. If it were me I would automate the direct email with a little bit of weak validation such as "please explain in one or two sentences your situation" then anyone who emails with a few words are automatically validated and any blank or one word emails are either auto-deleted or put aside for manual validation.
Just an idea though. I figure posting to HN means you wanted a little feedback :)
Best of luck with your book. I don't have a need for it right now (thankfully) but I hope it helps others as it appears you have a put a lot of thought and work into it.