terraform/juju/bosh are purpose-build for app and infra deployments.
StackStorm is a generic automation platform with no . One can use it to run arbitrary chain of actions on events. As such, it is used in auto-remediation & automating runbooks. We internally use it for variety of things like irc-to-slack relay, zombie ec2 vm periodic clean-up, ChatOps-ing JIRA, etc.
Some folks do run complex continuos deployment pipelines and blue/green deployments on StackStorm. Would be good if they can comment here.
may be, when it comes to CI/CD. not familiar with concourse.
my comment above got cut out, i meant to say "generic platform with no focus on CI/CD". It's for auto-remediation.
it's not natural to use bosh or concourse to automate cleaning up log files or replacing a failed node in cassandra ring, or respond to identified DDOS attack.