I've written a script to add Webmention support for static sites. It's available from:
All software that generates static web sites also creates ATOM XML files with the recent content (like Gruta, the one that build this site). By running this script on the ATOM you just generated, it posts Webmentions to every link found there and that has its support announced in
link tags inside its HTML.
It's written in Python with minimal external dependencies.