I welcome alternatives. It's been tough wrestling with Firecracker and OCI images. Kata container is also tough.
Microsandbox does not offer a cloud solution. It is self-hosted, designed to do what E2B does, to make it easier working with microVM-based sandboxes on your local machine whether that is Linux, macOS or Windows (planned) and to seamlessly transition to prod.
> Do you also use Firecracker under the hood?
It uses libkrun.