I have a #RightSortOfMad folder in my browser's bookmarks bar, full of links to ridiculous software. Occasionally I read the code, which is always a work of genius art. Today, added to the Right Sort Of Mad folder ... https://github.com/gh2o/bash_tls/blob/master/bash_tls.sh
bash_tls/bash_tls.sh at master · gh2o/bash_tls

A minimal TLS 1.2 client implementation in a pure Bash script - gh2o/bash_tls

GitHub