There are two special auto load folders that can be used to automatically load data files and DED definitions.
Mod makers can use this feature to auto-load any definitions or resources their mod requires from within a container. This is the recommended way to package your mod but it is also possible to install files directly into these “auto load” folders. See containers for information on how to use this feature in containers.
These folders are:
Data/ [game]/ Auto/
Defs/ [game]/ Auto/
All WAD, PK3, ZIP and LMP (Lump) files placed in the Data\[Game]\Auto\ directory will be automatically loaded at startup. The data files are loaded in alphabetical order, including all the subdirectories of the Auto directory.
All DED files placed in the Defs\[Game]\Auto\ directory will be automatically read at startup. The definition files are also loaded in alphabetical order, including all the subdirectories of the Auto directory.
Virtual files (from a PK3 or a WAD) in the Auto directories will also be loaded.