Nothing prevents storing pipeline configuration in git and syncing it to Spinnaker.
Foremast is a community provided solution that accomplishes much of this.
We’ve also added the ability to optionally lock a pipeline and prevent any modification from being made via the UI. In such scenarios the Spinnaker API is the only way that pipelines can be updated.
Further, we’re working on an improved way to manage pipeline templates and re-use/extend them across different applications (imagine having a common best practice pipeline that any application can extend and override as appropriate).
This will certainly support sourcing pipeline details stored outside of Spinnaker.
Suspect this feature (that we’re calling managed pipeline templates) will be available for public testing in the next month or so.