diff --git a/src/constants.hpp b/src/constants.hpp
index d82594937..b2caed061 100644
--- a/src/constants.hpp
+++ b/src/constants.hpp
@@ -28,8 +28,8 @@
 #include <complex>
 
 const int major_version = 5;
-const int minor_version = 8;
-const int revision      = 7;
+const int minor_version = 9;
+const int revision      = 0;
 
 /// NIST value for the inverse fine structure (http://physics.nist.gov/cuu/Constants/index.html)
 const double speed_of_light = 137.035999139;