Comment by superkuh

Receiving webmentions can be as simple as making a custom log in nginx and just having it save all POST to the webmention URL endpoint. I love it. And sending can be done with curl or whatever you want (ie html forms without JS).

Or, you can use any of the many community projects which handle all this backend stuff and provide it as a service.

Either extreme works. I love the indieweb set of protocols for this. Other things like ActivityPub require active interaction for the cryptographic handshake at a minimum and make simple solutions infeasible despite other benefits. Indieweb can be as complex or as simple as you want.