The Microsoft CLI tool available here. This tool is an official Microsoft solution that will be in public preview soon and will be supported by microsoft. It does not support some of the extra functionality of aws-runas but we encourage everyone to test it as a potential solution. (Especially those that don't take advantage of the extra features available with aws-runas). We will be creating documentation to share that will help users configure this tool.
These are amd64 or Intel binaries unless otherwise indicated by the binary. There are also arm and universal binaries.
Download the binary you need available here
unzip the binary of choice and then ensure execute permissions exist on linux and mac
shell
chmod u+x aadawscli # on linux and mac, windows .exe should be ready to go