dup: callback handler

source/architecture/core.md

@@ -106,19 +106,6 @@ Examples of types of information handled:
 - handle data generated by MaSA, like a check-in to an event.
 
 
-## Callback handlers
-
-Callback handlers are vendor-specific web applications offering a RESTful API to receive information about the lifecycle changes of the passes within the holder's wallet from the vendor.
-They pass this information to the event system.
-
-For example, the callback gets a request when the pass holder stores or deletes a pass to the wallet on their device.
-
-The web applications will be implemented using Python and the FastAPI framework.
-There will be a Python package for each vendor, at first:
-
-- `edutap.callback_google`
-- `edutap.callback_apple`
-
 ## Pass Management
 
 Pass management is the task, of creating and designing passes and then offering those passes to potential users, here called tappers.