Just wanted to play around with a few tools that these companies might be using.
Thanks for asking this question. I never thought about it. I just use chrome dev tools and thought that was all there was.
what about stackshare it one of my favorites, you can check some of others known companies stacks at http://stackshare.io/stacks
Why do you try to copy some company's stack? They have their own requirements and reasons why they decided to use that particular software.
You should, rather than copying, take your needs and decide based on that what kind of stacks you want to play around with.
BuiltWith - is another service that provides a great overview of what different websites are build with. Information like:
It's not 100% accurate, but it's closer than any other service I've used. Here is the result when I tried to search Hashnode.
P.S You can easily combine it with Wappalyzer, mentioned by @dhayanandhan.
You could use https://wappalyzer.com/ which predicts the tech stack of the website. I use wappalyzer chrome extension to quickly find out the tech behind a website.
This tool can't predict the server stack if they remove all headers though.
The Social Guy
Alexandre Lalung
Web Developer
You should look at https://siftery.com/, it's nice :)