I use procmail, fetchmail and nmh via mh-e. Never used imap and the only email service account I have is with lavabit. Each email is one file so the only filter

I use procmail, fetchmail and nmh via mh-e. Never used imap and the only email service account I have is with lavabit. Each email is one file so the only filtering is which folder the file goes to. Procmail does that and mairix finds them. I just have to write and read, maybe answer or delete.