FreeNAS Corral has let the docker genie out of the bottle, but I share your reservations about embedding Linux tech in a FreeNAS install. If the presence of docker detracts from and belittles the use of jails, I see that as a negative. But then, I don't need a NAS stuffed with apps. I'd like to see FreeNAS promote and exploit the strengths of FreeBSD. I believe they are to adopt the latest version of iocage.