> ODMG (and Magma) seem to block application evolution by storing the binary 
> objects so that class definitions can't change. It will be difficult to use 
> them in critical applications if this is correct.

Just to clarify, Magma now supports live-class evolution and the ability for
instances of many different generations of domain classes to exist in the
repository simultaneously, and there is no need for big-bang conversions.

Of course, this puts more burden on domain code.  There is only one definition
of the class active in the image, it must be prepared to handle objects of any
generation.

 - Chris