This looks great to me. I used to use Mendeley (until Elsevier bought it and locked me out - I forgot my Mendeley password but telling the app this just takes you to the Elsevier signup page?) and though Zotero is good, I have never liked it in terms of look and feel.

One nitpick:

Why jendeley?

As programmers, we require various documents in different formats, such as recent machine learning papers, classic compiler books, CPU and accelerator specification documents, programming language documents, and [...]

This is true for any researcher. I have an absolutely huge document library...and it has nothing to do with programming. I do keep a small repository of useful texts and articles in my development directory, but I'm not a computer scientist; I write code as a means to an end and have no ambitions to run a team or publish a library.