Maurice, you may or not be interested in being made aware of this:
https://github.com/RealDeuce/tith
TITH is a modern store-and-forward protocol for FidoNet Technology Networks. >It combines a small set of versioned standards with a Rust reference mailer, >with the goal of making secure FTN transport straightforward to implement and >interoperate with.
The project starts from a deliberately simple premise: define one canonical >representation, authenticate every peer and payload, and keep legacy >conversion at an explicit boundary instead of carrying historical ambiguity >into the native protocol.
By the maintainer of Syncterm
It's not quite done yet.
--
-Andy Alt
... NoCarrierMail, the new multi-platform, multi-format offline reader!
=== NoCarrierMail/Linux v0.55
--- SBBSecho 3.37-Win32
* Origin: X-Bit BBS > Oregon USA > x-bit.org/info (1:105/44)