Their routers are OpenWrt compatible by design, the factory firmware is based on owrt or you can flash upstream for a "pure" image. I've used them for many years and they're great.
I really like them too. Not only are they OpenWRT compatible, they run more or less stock OpenWRT with a custom UI. They do also expose the standard LuCi for advanced settings too.
Their routers are OpenWrt compatible by design, the factory firmware is based on owrt or you can flash upstream for a "pure" image. I've used them for many years and they're great.