This script came about due to the poor support for automating Let's Encrypt for the common use case of a root + wildcard certificate if using the "Joker" registrar's built-in DNS services.
It was expanded upon as even for the few tools that worked with that provider none of them supported modern ECDSA account keys and few if any supported ECDSA certificate generation.
A friend read the script after I was finished writing it and showed them a copy, and suggested I publish it on github as others may both find it useful to learn how Let's Encrypt works or may be in a similar situation I was in.
Most of the documentation is in the wdfcert script itself.
Finally: Why wdfcert? It's something I do for 'throwaway' one-off tools: With the name of Wolf it's a common typographical failure of various fonts that merges the ol into a d so wolf -> wdf