Right after writing Signed GPG keys and keyservers, Wiktor contact me, suggesting that using a Web Key Directory might be the better approach to solving my signed-keys-exchange problem. He also noticed that I had uploaded my GPG key in the wrong format, so receiving it via WKD only worked for GnuPG users.
Because of that I thought about playing a little bit around with how URLs are calculated for WKD and create a little validation utility:
$ wkd-validate 'email@example.com' $ wkd-validate 'firstname.lastname@example.org' 11:45AM FTL Failed to validate WKD content. error="received status code 404 while fetching key via WKD"
You can find the implementation on Github