Customisable workflow

I often find that I raise an issue to a team member, and then want to be notified when a ticket has been addressed and needs to be tested. Unfortunately, there appears to be no way to do that in Bitbucket - they either mark it as resolved and then I have no idea which ones have been tested or not, or they simply post a comment which means I have to pick up on that. Is there not some way of either adding a workflow for "ready for testing" or similar?