Torrent server with seed speed?

Question

bittorrent

We need a torrent client purely for distribution with approximately the following algorithm:
- if, apart from this computer, the distribution is 100% available (from other exchange participants) - the upload speed will be the same,
- if only this computer can seed - the speed is different.
Desirable lack of GUI and cross-platform.

Answer 1

seedbox.org.ua/