--- a/docs/HISTORY.txt	Tue Jul 17 11:12:44 2018 +0200
+++ b/docs/HISTORY.txt	Fri Jul 20 12:45:59 2018 +0200
@@ -1,6 +1,13 @@
 History
 =======
 
+0.1.17
+------
+ - use BTree to store image thumbnails and reduce conflicts
+ - updated SVG content-type checks
+ - rename IThumbnail interface to IThumbnails
+ - small code optimizations
+
 0.1.16.1
 --------
  - corrected image rendering function