diff --git a/service/syncer/syncer.go b/service/syncer/syncer.go
index d65bc374..78194d3d 100644
--- a/service/syncer/syncer.go
+++ b/service/syncer/syncer.go
@@ -67,8 +67,7 @@ func (s *Synchronizer) Sync(ctx context.Context, user *core.User) (*core.Batch,
 		// a panic that should absolutely never happen.
 		if err := recover(); err != nil {
 			logger = logger.WithField("error", err)
-			logger.Errorln("syncer: unexpected panic")
-			debug.PrintStack()
+			logger.Errorf("syncer: unexpected panic\n%s\n", debug.Stack())
 		}
 
 		// when the synchronization process is complete