If you are comfortable writing a Stash plugin there are events for when a PR is created/updated, which you can listen too and then update your CI system.
Some links which may help:
Quite possibly someone has already written something for your CI. Which CI server are you using?
Atlassian Summit is an excellent opportunity for in-person support, training, and networking.Learn more
Hello Community! My name is Claire Maynard, and I’m a Product Marketing Manager on the Bitbucket team. I’m interested in hearing what advice or tips you have for new users getting started on ...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
You're one step closer to meeting fellow Atlassian users at your local meet up. Learn more about AUGs