I had been thinking about the filtering part of #fcli, my #Mastodon to #email bridge as 'similar to #procmail', but today I realised that if I add custom headers to the email messages it produces I can just use procmail itself. By interfacing #Fediverse ideas with email standards I seem to be needing less and less custom code to get a setup which works for me, and making more and more use of decades old open source software, which is actually a pretty great outcome.