How can I flash openwrt image on routerboard 433GL?
why openwrt required? which router functionality can not run in routeros but in openwrt can? you can run openwrt as meta router.
I need it for ruby
You’d better ask this question on OpenWRT’s forum. Support never answers this type of questions, and other RouterOS users are unlikely to ever even try to install non-RouterOS software on RouterBOARDs.