diff --git a/specification/README.md b/specification/README.md
index 6582d0bc8344456b0f0a7e02ecf099e49eb7263a..e712c3436243add25f7b63bc7928322dcd7a9b80 100644
--- a/specification/README.md
+++ b/specification/README.md
@@ -33,6 +33,10 @@ Each platform is responsible to handle that requested data, that means for MVP e
   
 ![](https://git.fairkom.net/fairsync/maps/-/raw/master/diagrams/FairSync_Componentmodel.png)
 
+ArchitecturModel für Adapter zu iCal, ?Activity?...
+---------------------------------------------------
+Todo
+
 Technical implementation
 ------------------------
 The data exchange between the platforms is done via [REST](https://de.wikipedia.org/wiki/Representational_State_Transfer).