Master is now 1.1.0-dev.
diff --git a/tools/doxygen/Doxyfile.c++.internal b/tools/doxygen/Doxyfile.c++.internal
index 1473594..945298b 100644
--- a/tools/doxygen/Doxyfile.c++.internal
+++ b/tools/doxygen/Doxyfile.c++.internal
@@ -40,7 +40,7 @@
# could be handy for archiving the generated documentation or if some version
# control system is used.
-PROJECT_NUMBER = 1.0.0-pre1
+PROJECT_NUMBER = 1.1.0-dev
# Using the PROJECT_BRIEF tag one can provide an optional one line description
# for a project that appears at the top of each page and should give viewer a