diff --git a/docs/change-log.yaml b/docs/change-log.yaml
index a67b83da..1662225c 100644
--- a/docs/change-log.yaml
+++ b/docs/change-log.yaml
@@ -1,3 +1,11 @@
+v0.5.9:
+  api-change:
+    array:
+    - do not check internal bitmap size, just panic; by drdr xp; 2019-06-02
+  new-feature:
+    array:
+    - add ExtendIndex to allocate additional 0-bits after Bitmaps and Offsets; by drdr
+      xp; 2019-05-28
 v0.5.8:
   new-feature:
     slimtrie:
diff --git a/docs/change-log/v0.5.9.yaml b/docs/change-log/v0.5.9.yaml
new file mode 100644
index 00000000..19dd2fa0
--- /dev/null
+++ b/docs/change-log/v0.5.9.yaml
@@ -0,0 +1,7 @@
+api-change:
+  array:
+  - do not check internal bitmap size, just panic; by drdr xp; 2019-06-02
+new-feature:
+  array:
+  - add ExtendIndex to allocate additional 0-bits after Bitmaps and Offsets; by drdr
+    xp; 2019-05-28