Create (or Import?) a Workflow via REST API

Is it possible to create a workflow via REST API? We will be creating new issues via REST API from our application and we then will need this issues trigger a workflow upon any comment add/update/delete operation, with the workflow set to send an email, or post to an Amazon SQS queue or perhaps just do an HTTP Post to notify our app that there was a new/changed/deleted comment. eMail or, better yet, a queue allows us to decouple our app and YouTrack. We have already done a POC where we manually create an email workflow with a specific issue as a prerequisite, but now we want to be able to do so via REST API. As an alternative, again, via the API, we would want to change the pre-requisites in our manually created workflow to add/remove the prerequisite issues. Is it possible to do so? Is there an alternative way of accomplishing this? Or, perhaps there is a way to programmatically 'import' a workflow? Note that we do NOT want to auto-attach this workflow to new projects, as we will have projects that we do not want to 'publish' the comments change notifications  to our app,