--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -537,6 +537,13 @@ set(SRC_DRIVERS_SDL
 
 set(SOURCES ${SRC_CORE} ${SRC_DRIVERS_COMMON} ${SRC_DRIVERS_SDL})
 
+# Put build timestamp into BUILD_TS environment variable and from there into
+# the FCEUX_BUILD_TIMESTAMP preprocessor definition.
+# Note: with CMake >= 3.8.0, this will respect SOURCE_DATE_EPOCH. For more info,
+#       see <https://reproducible-builds.org/docs/source-date-epoch/>.
+string(TIMESTAMP BUILD_TS "%Y-%m-%d %H:%M:%S")
+add_definitions( -DFCEUX_BUILD_TIMESTAMP=\"${BUILD_TS}\" )
+
 if (WIN32)
 add_custom_command( 
 	OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/fceux_git_info.cpp  
--- a/src/config.cpp
+++ b/src/config.cpp
@@ -48,7 +48,8 @@ const char *FCEUI_GetAboutString(void)
 		"of NES emulation. In Memoriam --\n"
 		"ugetab\n"
 		"\n"
-		__TIME__ " " __DATE__ "\n";
+		"\n"
+		FCEUX_BUILD_TIMESTAMP "\n";
 
 	if (aboutString) return aboutString;
 
