I thought I could say a few words on the differences between FeatureServer and MapFish Server.
First, FeatureServer and MapFish Server have similarities. They share a similar, REST-based protocol, for creating, reading, updating and deleting features.
The main difference between the two: FeatureServer is a standalone application, MapFish Server is a web-mapping development framework.
FeatureServer is perfect for very rapidly setting up editable layers, with no custom needs. MapFish Server is good if you work on a customer project, with specific, customer-oriented needs; MapFish
Two different goals.