Hi Oliver,
I'm in a similar boat :)
I'm just now picking up a partially completed project of mine that's been shelved since last year and have run into plenty of regressions and plain old changes as I bring the various components up to date. There's a lot of moving parts.
eg: Vagrant 1.6.x -> 1.7.x, Packer 0.6.x -> 0.8.x, Salt 2014.1 -> 2015.x, Ubuntu 12.04 -> 14.04, and Windows 2008R2 -> 2012R2. And moving the Windows communicators from cygwin SSH/Bash to WinRM/Powershell. Things would be much easier without Windows that's for sure.
Although I'm not a devloper, I'm ok with Python. My only tiny Ruby experience though is (ironically I suppose) submitting a minor vagrant salt provisioner (on Windows) fix last year. I suspect Packer will be sending me to the Go tutorial too.
I'll look through your Trello board to see if I can help out anywhere.
Cheers
Anton