Plenty of other sites have already brought this up, but I wanted to have it referenced here for myself. I gave it a shot for myself & while I think I followed it all the way through, still seem to be missing the root access part. Will have to give it another round & see which step I may have missed.
GitHub: marcosscriven/galeforce
Here is where I ran into the issue. At this point you should be able to login as root:
ssh root@192.168.86.1
Password: changeme
And for the love of god... Please, Please, PLEASE, make the first thing you do, is change the password. If you're running through this process, you're probably already a bit of a g33k, so changing the password should already be the first thing on your mind.
For those who aren't g33ks, the password can be changed with the [passwd](http://man7.org/linux/man-pages/man1/passwd.1.html)
command
EDIT 20170723-0912EST: Yesterday I had opened an issue on the galeforce repo, with the problem I was having (listed above): Solid Purple But No SSH? #3. marcosscriven responded to me, to lend a hand to me & another user that was having the same issue. I'm assuming my problem was definitely user-related, so I gave the process another shot.
I followed the exact same process, except this time I used the OnHub Recovery Utility to make the USB drive. After that, I was all set!
[caption id="attachment_20" align="alignnone" width="225"] A Google WiFi device in Developer Mode[/caption]