A request to store, in first data store associated with a customer of a computing resource service provider, a software image is received, the request including a set of layers of the software image to be stored. As a result of successful authentication of the request, based at least in part on a security token included with the request, a subset of layers of the software image that have not previously been stored in the first data store are determined, based at least in part on first metadata obtained from a second data store, the subset of layers in the first data store are stored, second metadata about the subset of layers are stored in the second data store, and the software image is caused to be launched in a software container of an instance based at least in part on the subset of layers.