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OverlaysThere are two types of overlays:
File OverlaysFile overlays allow injection of content at the beginning or end of a file. Use the <fileoverlays> and <fileoverlay> elements in the tagneticconfig configuration file to set these up.
File overlays are useful for declaring application-wide variables and set-up.
Tag OverlaysTag overlays match a particular tag, and then either inject content:
Document the scope implications on the ordering of overlays with other tags.