Is dead. doesn't come up on restart, has errors in logs.
The error comes from the fact that the current version checked out on the server is not up-to-date, thus having problems loading the config.
However, we are running into issues when deploying the changes. Concretely, the checkout stage fails because trebuchet is not able to find the submodule's newest ref (which is present in a normal check-out), as seen in P402 . Citoid's deployment config (in role::deployment) seems to be alright, the contents in /srv/deployment/citoid/deploy on tin as well.
So after some investigation it became obvious the trebuchet could not update the git submodule for citoid. The error was
output: fatal: reference is not a tree: 2cd246b99fd2f407b92c33a079a1120f0abe7117
The repository on tin had the commit but would not advertise it. The solution was to
tin:/srv/deployment/citoid/deploy/src$ git update-server-info
The good news is that on very first failed restart on a host, trebuchet refused correctly to restart the service on the other one so the service had 0 downtime (hence my marking of the task as not blocking anything)
The problem has now changed into
Error: Cannot find module 'bunyan'
which is being look into by @mobrovac