Portability Concerns
Developers worry that the applications will not be portable from App Engine and fear being locked into the technology. In response, there are a number of projects to create open-source back-ends for the various proprietary/closed APIs of app engine, especially the datastore. Although these projects are at various levels of maturity, none of them are at the point where installing and running an App Engine app is as simple as it is on Google's service. AppScale and TyphoonAE are two of the open source efforts.
AppScale can run Python, Java, and Go GAE applications on EC2 and other cloud vendors.
TyphoonAE can run python App Engine applications on any cloud that support linux machines.
Web2py web framework offers migration between SQL Databases and Google App Engine, however it doesn't support several App Engine-specific features such as transactions and namespaces.
Read more about this topic: Google App Engine
Famous quotes containing the word concerns:
“In common with other rural regions much of the Iowa farm lore concerns the coming of company. When the rooster crows in the doorway, or the cat licks his fur, company is on the way.”
—For the State of Iowa, U.S. public relief program (1935-1943)