diff --git a/module_build_service/builder/KojiModuleBuilder.py b/module_build_service/builder/KojiModuleBuilder.py
index 5e49df67..1c98d81d 100644
--- a/module_build_service/builder/KojiModuleBuilder.py
+++ b/module_build_service/builder/KojiModuleBuilder.py
@@ -292,6 +292,7 @@ chmod 644 %buildroot/%_rpmconfigdir/macros.d/macros.modules
 
         tagged_nvrs = self._get_tagged_nvrs(self.module_build_tag['name'])
 
+        self.koji_session.multicall = True
         for nvr in artifacts:
             if nvr in tagged_nvrs:
                 continue
@@ -306,18 +307,21 @@ chmod 644 %buildroot/%_rpmconfigdir/macros.d/macros.modules
                 name = kobo.rpmlib.parse_nvr(nvr)['name']
                 log.info("%r adding %s to group %s" % (self, name, group))
                 self.koji_session.groupPackageListAdd(build_tag, group, name)
+        self.koji_session.multiCall(strict=True)
 
     def tag_artifacts(self, artifacts):
         dest_tag = self._get_tag(self.module_tag)['id']
 
         tagged_nvrs = self._get_tagged_nvrs(self.module_tag['name'])
 
+        self.koji_session.multicall = True
         for nvr in artifacts:
             if nvr in tagged_nvrs:
                 continue
 
             log.info("%r tagging %r into %r" % (self, nvr, dest_tag))
             self.koji_session.tagBuild(dest_tag, nvr)
+        self.koji_session.multiCall(strict=True)
 
     def wait_task(self, task_id):
         """
@@ -354,7 +358,13 @@ chmod 644 %buildroot/%_rpmconfigdir/macros.d/macros.modules
         #  * we do want only build explicitly tagged in the module tag (inherit: False)
 
         opts = {'latest': True, 'package': artifact_name, 'inherit': False}
-        tagged = self.koji_session.listTagged(self.module_tag['name'], **opts)
+
+        if artifact_name == "module-build-macros":
+            tag = self.module_build_tag['name']
+        else:
+            tag = self.module_tag['name']
+
+        tagged = self.koji_session.listTagged(tag, **opts)
 
         if tagged:
             assert len(tagged) == 1, "Expected exactly one item in list. Got %s" % tagged