Firecracker-bootable Linux kernel builds, published as GitHub Releases, used as the default images in Hyper.
Hyper allows you to provide your own vmlinux images. It is, however,
convenient, not to have to worry about providing your vmlinux images, so by
default, Hyper will fetch images from the Github Releases of this
repo. These are all
checksummed in Hyper's implementation to mitigate the risk of a supply chain
attack.