routeros-GPL

AFAIK, for a long they were pretty hostile and there's still this webpage which asks a $45 wire transfer in order to receive a CD with open source components used in the routerOS: https://mikrotik.com/downloadterms.html That might have changed now, but I still can't find an official repo. You could look for older versions like this: https://github.com/robimarko/routeros-GPL or try to contact them directly (or sue if you think you have a standing).

Which is Linux based, yet Mikrotik seems somewhat reluctant to honor the spirit of the GPL... https://forum.mikrotik.com/viewtopic.php?t=100803 https://github.com/robimarko/routeros-GPL

Supposedly its available by request (which is all that is required by GPL). An old-ish copy is here: https://github.com/robimarko/routeros-GPL

It seems they comply https://github.com/robimarko/routeros-GPL

Some info here: https://forum.lede-project.org/t/mikrotik-gpl-source/6750/12 Which led to this repo: https://github.com/robimarko/routeros-GPL