Happy to have completed my first Rust app that is actually useful to me, every minute of the day. This replaces a truly ancient piece of mixed C and C++ code taking care of filtering email through SpamAssassin on my mail server.
This is extremely niche, and probably only interesting to old-school mail server enthusiasts. Bit of an exercise really. But who knows – somebody might still find it interesting for some other reason. Keywords: command-line application, system service, C callback API, SMTP, milter, ancient technologies, Postfix, Apache SpamAssassin, free software.