You need a nightly rust toolchain installed (use rustup for that) and QEMU.
Install an OVMF Snapshot from Kraxel like:
https://www.kraxel.org/repos/jenkins/edk2/edk2.git-ovmf-x64-0-20190131.912.g3b6c73f13e.noarch.rpm
$ git submodule update --init $ ./build.sh
$ ./run.sh
Break into the EFI menu by hitting escape. Then execute:
Shell> \UEFI-APP.EFI
This is just a version of Gil Mendes' blog post with the build.py file replaced with simple shell scripts ported to the latest uefi-rs tree. See:
https://medium.com/@gil0mendes/an-efi-app-a-bit-rusty-82c36b745f49
