Install both versions of UEFITool, the one with the old engine and the new one. It's not possible to use both packages in the same environment, since there is a collision between the names of the binary files. To make sure a specific package is used, a new environment needs to be spawned with the following command: $ nix-shell -p <package_name> The UEFITool binaries can be executed from the shell then. Change-Id: Ia5d679c6e7cd01c2ab819bd6c085596a926c494d Signed-off-by: Felix Singer <felix.singer@secunet.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/57624 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Paul Menzel <paulepanter@mailbox.org> Reviewed-by: Michael Niewöhner <foss@mniewoehner.de>