Synchronet v3.18b-Win32 (install) has been released (Sept-2020).
Synchronet v3.19a, now under development, requires libarchive-dev to build successfully.
You can donate to the Synchronet project using PayPal.
Servers
Synchronet's TCP/IP Servers are in-process native binaries (in the form of dynamically loadable libraries and shared objects), written primarily in C (with very little C++).
Configuration
Synchronet's Servers are enabled/disabled and configured in the ctrl/sbbs.ini file.