Swift has a very fortunate position here. Specifically, the interaction surface is very low (mainly user app<->Swift and Glance<->Swift) and the interface is very restricted. It's just an object store.

It may be a great project for migration, just like Glance (although that one doesn't need that much performance).

The projects I don't think will ever be able to move are Neutron and Nova. Even parts of Nova are so tightly connected that it would need a major redesign before rpc can really split scheduler and other pieces into different projects. Also Keystone probably has too many integration layers / plugins by now to migrate to anything.

(I'm glad that this happened BTW, the more languages in OpenStack, the better isolated and simpler the interfaces will become)