There is an option in “Window -> Preferences -> Aptana Studio -> Editors” called “Save Actions: Remove trailing whitespace characters”. However, even when it’s checked, it doesn’t seem to work for me. So… I followed the instructions here (http://jelaniharris.com/2012/strip-whitespace-on-save-with-aptana/) and installed the AnyEdit plugin. After a restart, hey presto. It just works. Although Aptana 3.2 uses Eclipse 3.7, and AnyEdit plugin states it’s for Eclipse 3.5, it still works fine (for me).