CodeReady Containers runs an OpenShift cluster on a laptop or workstation using virtualization. It's written in go, and uses KVM, HyperV or HyperKit depending on the OS it's running on. External network access is done through gVisor's userland TCP/IP stack which the virtual machine uses over virtio-vsock. This talk will start with a short presentation of what CodeReady Containers is, explain why it needs a userland TCP/IP stack, but its main focus will be around virtio vsock, how to use it from go, and the differences to expect on the different hypervisors.