diff --git a/HISTORY.txt b/HISTORY.txt
index 49c0a539..23e380a3 100644
--- a/HISTORY.txt
+++ b/HISTORY.txt
@@ -1,3 +1,5 @@
+18.5.12:
+ - Switch to calver for versioning.
 11.10.4:
  - Bugfix release (_mkstmp_inner backport breaks python3.4/3.5 compat)
 11.10.3: