diff --git a/tests/base.py b/tests/base.py
index 2c478ad433..61e1deb8af 100755
--- a/tests/base.py
+++ b/tests/base.py
@@ -1180,7 +1180,7 @@ class FakeBuild(object):
         self.log.debug("Build %s continuing" % self.unique)
 
         result = (RecordingAnsibleJob.RESULT_NORMAL, 0)  # Success
-        if (('ZUUL_REF' in self.parameters) and self.shouldFail()):
+        if self.shouldFail():
             result = (RecordingAnsibleJob.RESULT_NORMAL, 1)  # Failure
         if self.aborted:
             result = (RecordingAnsibleJob.RESULT_ABORTED, None)
@@ -1215,8 +1215,7 @@ class FakeBuild(object):
             except NoSuchPathError as e:
                 self.log.debug('%s' % e)
                 return False
-            ref = self.parameters['ZUUL_REF']
-            repo_messages = [c.message.strip() for c in repo.iter_commits(ref)]
+            repo_messages = [c.message.strip() for c in repo.iter_commits()]
             commit_message = '%s-1' % change.subject
             self.log.debug("Checking if build %s has changes; commit_message "
                            "%s; repo_messages %s" % (self, commit_message,
diff --git a/tests/unit/test_scheduler.py b/tests/unit/test_scheduler.py
index d4290a91dd..e995d89df8 100755
--- a/tests/unit/test_scheduler.py
+++ b/tests/unit/test_scheduler.py
@@ -4776,12 +4776,10 @@ class TestSchedulerMerges(ZuulTestCase):
         self.waitUntilSettled()
 
         build = self.builds[-1]
-        ref = self.getParameter(build, 'ZUUL_REF')
-
         path = os.path.join(build.jobdir.src_root, 'review.example.com',
                             project)
         repo = git.Repo(path)
-        repo_messages = [c.message.strip() for c in repo.iter_commits(ref)]
+        repo_messages = [c.message.strip() for c in repo.iter_commits()]
         repo_messages.reverse()
 
         self.executor_server.hold_jobs_in_build = False
@@ -4848,12 +4846,11 @@ class TestSchedulerMerges(ZuulTestCase):
 
         build = self.builds[-1]
         self.assertEqual(self.getParameter(build, 'ZUUL_BRANCH'), 'mp')
-        ref = self.getParameter(build, 'ZUUL_REF')
         path = os.path.join(build.jobdir.src_root, 'review.example.com',
                             'org/project-merge-branches')
         repo = git.Repo(path)
 
-        repo_messages = [c.message.strip() for c in repo.iter_commits(ref)]
+        repo_messages = [c.message.strip() for c in repo.iter_commits()]
         repo_messages.reverse()
         correct_messages = [
             'initial commit',
@@ -4889,16 +4886,14 @@ class TestSchedulerMerges(ZuulTestCase):
         for job in self.builds:
             if 'project-merge' in job.name:
                 job_A = job
-        ref_A = self.getParameter(job_A, 'ZUUL_REF')
         commit_A = self.getParameter(job_A, 'ZUUL_COMMIT')
-        self.log.debug("Got Zuul ref for change A: %s" % ref_A)
         self.log.debug("Got Zuul commit for change A: %s" % commit_A)
 
         path = os.path.join(job_A.jobdir.src_root, 'review.example.com',
                             'org/project-merge-branches')
         repo = git.Repo(path)
         repo_messages = [c.message.strip()
-                         for c in repo.iter_commits(ref_A)]
+                         for c in repo.iter_commits()]
         repo_messages.reverse()
         correct_messages = [
             'initial commit', 'add content from fixture', 'A-1']
@@ -4911,16 +4906,13 @@ class TestSchedulerMerges(ZuulTestCase):
         for job in self.builds:
             if 'project-merge' in job.name:
                 job_B = job
-        ref_B = self.getParameter(job_B, 'ZUUL_REF')
         commit_B = self.getParameter(job_B, 'ZUUL_COMMIT')
-        self.log.debug("Got Zuul ref for change B: %s" % ref_B)
         self.log.debug("Got Zuul commit for change B: %s" % commit_B)
 
         path = os.path.join(job_B.jobdir.src_root, 'review.example.com',
                             'org/project-merge-branches')
         repo = git.Repo(path)
-        repo_messages = [c.message.strip()
-                         for c in repo.iter_commits(ref_B)]
+        repo_messages = [c.message.strip() for c in repo.iter_commits()]
         repo_messages.reverse()
         correct_messages = [
             'initial commit', 'add content from fixture', 'mp commit', 'B-1']
@@ -4933,15 +4925,12 @@ class TestSchedulerMerges(ZuulTestCase):
         for job in self.builds:
             if 'project-merge' in job.name:
                 job_C = job
-        ref_C = self.getParameter(job_C, 'ZUUL_REF')
         commit_C = self.getParameter(job_C, 'ZUUL_COMMIT')
-        self.log.debug("Got Zuul ref for change C: %s" % ref_C)
         self.log.debug("Got Zuul commit for change C: %s" % commit_C)
         path = os.path.join(job_C.jobdir.src_root, 'review.example.com',
                             'org/project-merge-branches')
         repo = git.Repo(path)
-        repo_messages = [c.message.strip()
-                         for c in repo.iter_commits(ref_C)]
+        repo_messages = [c.message.strip() for c in repo.iter_commits()]
 
         repo_messages.reverse()
         correct_messages = [
diff --git a/zuul/driver/gerrit/gerritconnection.py b/zuul/driver/gerrit/gerritconnection.py
index 8f8465afd3..98adc69b53 100644
--- a/zuul/driver/gerrit/gerritconnection.py
+++ b/zuul/driver/gerrit/gerritconnection.py
@@ -80,7 +80,7 @@ class GerritEventConnector(threading.Thread):
             patchset = data.get('patchSet')
             if patchset:
                 event.patch_number = patchset.get('number')
-                event.refspec = patchset.get('ref')
+                event.ref = patchset.get('ref')
             event.approvals = data.get('approvals', [])
             event.comment = data.get('comment')
         refupdate = data.get('refUpdate')
@@ -418,7 +418,7 @@ class GerritConnection(BaseConnection):
         files = []
         for ps in data['patchSets']:
             if ps['number'] == change.patchset:
-                change.refspec = ps['ref']
+                change.ref = ps['ref']
                 for f in ps.get('files', []):
                     files.append(f['file'])
             if int(ps['number']) > int(max_ps):
diff --git a/zuul/driver/github/githubconnection.py b/zuul/driver/github/githubconnection.py
index ff113ce2bf..c3cafba3b1 100644
--- a/zuul/driver/github/githubconnection.py
+++ b/zuul/driver/github/githubconnection.py
@@ -299,7 +299,7 @@ class GithubWebhookListener():
                                                       event.change_number)
         event.updated_at = pr_body.get('updated_at')
         event.branch = base.get('ref')
-        event.refspec = "refs/pull/" + str(pr_body.get('number')) + "/head"
+        event.ref = "refs/pull/" + str(pr_body.get('number')) + "/head"
         event.patch_number = head.get('sha')
 
         event.title = pr_body.get('title')
@@ -601,7 +601,7 @@ class GithubConnection(BaseConnection):
 
         self.log.info("Updating %s" % (change,))
         change.pr = self.getPull(change.project.name, change.number)
-        change.refspec = "refs/pull/%s/head" % change.number
+        change.ref = "refs/pull/%s/head" % change.number
         change.branch = change.pr.get('base').get('ref')
         change.files = change.pr.get('files')
         change.title = change.pr.get('title')
diff --git a/zuul/driver/sql/sqlreporter.py b/zuul/driver/sql/sqlreporter.py
index 214b667124..aca1b069ba 100644
--- a/zuul/driver/sql/sqlreporter.py
+++ b/zuul/driver/sql/sqlreporter.py
@@ -41,14 +41,14 @@ class SQLReporter(BaseReporter):
         with self.connection.engine.begin() as conn:
             change = getattr(item.change, 'number', '')
             patchset = getattr(item.change, 'patchset', '')
-            refspec = getattr(item.change, 'refspec', item.change.newrev)
+            ref = getattr(item.change, 'ref', '')
             buildset_ins = self.connection.zuul_buildset_table.insert().values(
                 zuul_ref=item.current_build_set.ref,
                 pipeline=item.pipeline.name,
                 project=item.change.project.name,
                 change=change,
                 patchset=patchset,
-                ref=refspec,
+                ref=ref,
                 score=self.result_score,
                 message=self._formatItemReport(
                     item, with_jobs=False),
diff --git a/zuul/driver/zuul/__init__.py b/zuul/driver/zuul/__init__.py
index 08612dcc91..0f6ec7da88 100644
--- a/zuul/driver/zuul/__init__.py
+++ b/zuul/driver/zuul/__init__.py
@@ -82,7 +82,7 @@ class ZuulDriver(Driver, TriggerInterface):
         event.branch = change.branch
         event.change_url = change.url
         event.patch_number = change.patchset
-        event.refspec = change.refspec
+        event.ref = change.ref
         self.sched.addEvent(event)
 
     def _createParentChangeEnqueuedEvents(self, change, pipeline):
@@ -104,7 +104,7 @@ class ZuulDriver(Driver, TriggerInterface):
         event.branch = change.branch
         event.change_url = change.url
         event.patch_number = change.patchset
-        event.refspec = change.refspec
+        event.ref = change.ref
         self.sched.addEvent(event)
 
     def getTrigger(self, connection_name, config=None):
diff --git a/zuul/executor/client.py b/zuul/executor/client.py
index beb8964fa8..49569ccf41 100644
--- a/zuul/executor/client.py
+++ b/zuul/executor/client.py
@@ -196,10 +196,10 @@ class ExecutorClient(object):
         params['ZUUL_PIPELINE'] = pipeline.name
         params['ZUUL_URL'] = item.current_build_set.zuul_url
         params['ZUUL_VOTING'] = job.voting and '1' or '0'
-        if hasattr(item.change, 'refspec'):
+        if hasattr(item.change, 'number'):
             changes_str = '^'.join(
                 ['%s:%s:%s' % (i.change.project.name, i.change.branch,
-                               i.change.refspec)
+                               i.change.ref)
                  for i in all_items])
             params['ZUUL_BRANCH'] = item.change.branch
             params['ZUUL_CHANGES'] = changes_str
diff --git a/zuul/executor/server.py b/zuul/executor/server.py
index ef5363c5ff..4448db8903 100644
--- a/zuul/executor/server.py
+++ b/zuul/executor/server.py
@@ -848,7 +848,7 @@ class AnsibleJob(object):
                                   project['name'])
             repos[project['canonical_name']] = repo
 
-        merge_items = [i for i in args['items'] if i.get('refspec')]
+        merge_items = [i for i in args['items'] if i.get('number')]
         if merge_items:
             if not self.doMergeChanges(merger, merge_items,
                                        args['repo_state']):
diff --git a/zuul/merger/merger.py b/zuul/merger/merger.py
index 93340faa51..c5d1f2ad55 100644
--- a/zuul/merger/merger.py
+++ b/zuul/merger/merger.py
@@ -225,9 +225,9 @@ class Repo(object):
         except AssertionError:
             origin.fetch(ref)
 
-    def fetchFrom(self, repository, refspec):
+    def fetchFrom(self, repository, ref):
         repo = self.createRepoObject()
-        repo.git.fetch(repository, refspec)
+        repo.git.fetch(repository, ref)
 
     def createZuulRef(self, ref, commit='HEAD'):
         repo = self.createRepoObject()
@@ -391,11 +391,11 @@ class Merger(object):
         try:
             mode = item['merge_mode']
             if mode == zuul.model.MERGER_MERGE:
-                commit = repo.merge(item['refspec'])
+                commit = repo.merge(item['ref'])
             elif mode == zuul.model.MERGER_MERGE_RESOLVE:
-                commit = repo.merge(item['refspec'], 'resolve')
+                commit = repo.merge(item['ref'], 'resolve')
             elif mode == zuul.model.MERGER_CHERRY_PICK:
-                commit = repo.cherryPick(item['refspec'])
+                commit = repo.cherryPick(item['ref'])
             else:
                 raise Exception("Unsupported merge mode: %s" % mode)
         except git.GitCommandError:
@@ -410,9 +410,10 @@ class Merger(object):
         return commit
 
     def _mergeItem(self, item, recent, repo_state):
-        self.log.debug("Processing refspec %s for project %s/%s / %s ref %s" %
-                       (item['refspec'], item['connection'],
-                        item['project'], item['branch'], item['ref']))
+        self.log.debug("Processing ref %s for project %s/%s / %s uuid %s" %
+                       (item['ref'], item['connection'],
+                        item['project'], item['branch'],
+                        item['buildset_uuid']))
         repo = self.getRepo(item['connection'], item['project'])
         key = (item['connection'], item['project'], item['branch'])
 
@@ -451,7 +452,7 @@ class Merger(object):
             zuul_ref = None
             try:
                 repo = self.getRepo(connection, project)
-                zuul_ref = branch + '/' + item['ref']
+                zuul_ref = branch + '/' + item['buildset_uuid']
                 if not repo.getCommitFromRef(zuul_ref):
                     repo.createZuulRef(zuul_ref, mrc)
             except Exception:
diff --git a/zuul/model.py b/zuul/model.py
index ed77864f90..ed501640e5 100644
--- a/zuul/model.py
+++ b/zuul/model.py
@@ -1841,12 +1841,10 @@ class QueueItem(object):
         patchset = None
         oldrev = None
         newrev = None
-        refspec = None
         branch = None
         if hasattr(self.change, 'number'):
             number = self.change.number
             patchset = self.change.patchset
-            refspec = self.change.refspec
         if hasattr(self.change, 'newrev'):
             oldrev = self.change.oldrev
             newrev = self.change.newrev
@@ -1860,9 +1858,9 @@ class QueueItem(object):
         return dict(project=project.name,
                     connection=connection_name,
                     merge_mode=self.current_build_set.getMergeMode(),
-                    refspec=refspec,
+                    ref=self.change.ref,
                     branch=branch,
-                    ref=self.current_build_set.ref,
+                    buildset_uuid=self.current_build_set.uuid,
                     number=number,
                     patchset=patchset,
                     oldrev=oldrev,
@@ -1951,7 +1949,6 @@ class Change(Branch):
         self.number = None
         self.url = None
         self.patchset = None
-        self.refspec = None
 
         self.needs_changes = []
         self.needed_by_changes = []
@@ -2008,6 +2005,7 @@ class TriggerEvent(object):
         # common
         self.type = None
         self.branch_updated = False
+        self.ref = None
         # For management events (eg: enqueue / promote)
         self.tenant_name = None
         self.project_hostname = None
@@ -2019,12 +2017,10 @@ class TriggerEvent(object):
         self.change_number = None
         self.change_url = None
         self.patch_number = None
-        self.refspec = None
         self.branch = None
         self.comment = None
         self.state = None
         # ref-updated
-        self.ref = None
         self.oldrev = None
         self.newrev = None
         # For events that arrive with a destination pipeline (eg, from