diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1df672e231..5fb1be18da 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -11,6 +11,10 @@ SET (CUTECASH_VERSION_MAJOR "0")
 SET (CUTECASH_VERSION_MINOR "1")
 SET (CUTECASH_VERSION_PATCH "0")
 
+# Change this in development versions when changing anything that
+# affects stored data structures. Reset to zero when bumping version.
+SET (CUTECASH_VERSION_NANO "0")
+
 # Extra cmake macros
 SET (CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/src/cmake_modules;${CMAKE_MODULE_PATH}")
 INCLUDE (MacroAppendForeach)
diff --git a/src/config.h.cmake.in b/src/config.h.cmake.in
index 4ef31dd6f4..d44124cd77 100644
--- a/src/config.h.cmake.in
+++ b/src/config.h.cmake.in
@@ -4,6 +4,7 @@
 #define GNUCASH_MAJOR_VERSION @CUTECASH_VERSION_MAJOR@
 #define GNUCASH_MICRO_VERSION @CUTECASH_VERSION_MINOR@
 #define GNUCASH_MINOR_VERSION @CUTECASH_VERSION_PATCH@
+#define GNUCASH_NANO_VERSION @CUTECASH_VERSION_NANO@
 #define VERSION "@CUTECASH_VERSION_MAJOR@.@CUTECASH_VERSION_MINOR@.@CUTECASH_VERSION_PATCH@"
 
 /* Definitions for all OS */