diff --git a/ChangeLog b/ChangeLog
index 483d5142..cb88ff16 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,6 @@
+25/3/17 started 8.5.1
+- init more classes earlier, thanks David
+
 13/10/16 started 8.5.0
 - rewritten buffer system is safer and frees memory earlier
 - added tiff save to buffer
diff --git a/configure.ac b/configure.ac
index d75d0d5e..0e9a43ce 100644
--- a/configure.ac
+++ b/configure.ac
@@ -18,7 +18,7 @@ AC_CONFIG_MACRO_DIR([m4])
 # user-visible library versioning
 m4_define([vips_major_version], [8])
 m4_define([vips_minor_version], [5])
-m4_define([vips_micro_version], [0])
+m4_define([vips_micro_version], [1])
 m4_define([vips_version],
           [vips_major_version.vips_minor_version.vips_micro_version])
 
@@ -38,7 +38,7 @@ VIPS_VERSION_STRING=$VIPS_VERSION-`date`
 #   binary interface changes not backwards compatible?: reset age to 0
 
 LIBRARY_CURRENT=49
-LIBRARY_REVISION=0
+LIBRARY_REVISION=1
 LIBRARY_AGE=7
 
 # patched into include/vips/version.h