KDE currently relies on QStandardPath for shared resource lookups.

QStandardPaths DataLocation, ConfigLocation, etc. return platform specific defaults but on Linux they also return the values from XDG_DATA_DIRS, XDG_CONFIG_DIRS, etc. so when installing applications in non default paths applications that use QStandardPaths can still find their data/libraries/plugins/config, etc.

QStandardPaths is not changable at runtime on OS X and Windows, which means the strategy of using QStandardPaths fails when KDE is deployed though eg homebrew.