Author here. Yeah, I'm hoping to use rkt instead of Docker when I actually put this all together. Docker wins for familiarity though, plus is the kubelet's default hence using it for this post.

Any pointers to some good docs? I'd love to start playing with rkt but I have no idea where to even start.

The really easy part is it can happily run Docker containers:

    $ sudo bin/rkt --insecure-skip-verify run --interactive docker://busybox
    rkt: fetching image from docker://busybox
    Downloading cf2616975b4a: [====================================] 32 B/32 B
    Downloading 6ce2e90b0bc7: [====================================] 1.15 MB/1.15 MB
    Downloading 8c2e06607696: [====================================] 32 B/32 B
    2015/08/28 12:15:24 Preparing stage1
    2015/08/28 12:15:25 Writing image manifest
    2015/08/28 12:15:25 Loading image sha512-9d710100ce6769569b12a39100318bfed5b6b98115ee6315b724c11658db3751
    2015/08/28 12:15:25 Writing pod manifest
    2015/08/28 12:15:25 Setting up stage1
    2015/08/28 12:15:25 Wrote filesystem to /var/lib/rkt/pods/run/e3cbf309-5f03-4ce4-b098-597b5ec3e040
    2015/08/28 12:15:25 Pivoting to filesystem /var/lib/rkt/pods/run/e3cbf309-5f03-4ce4-b098-597b5ec3e040
    2015/08/28 12:15:25 Execing /init
    / # ls -l $(which ls)
    lrwxrwxrwx    1 root     root             7 May 22  2014 /bin/ls -> busybox
    / # exit
    Sending SIGTERM to remaining processes...
    Sending SIGKILL to remaining processes...
    Halting system.

The `--insecure-skip-verify` is to disable the GPG verification that rkt does for its native ACI container format. Beyond that, take a look at `rkt help run` and poke around.