Grey Matter Fabric supports service discovery from AWS EC2 instances. See the Grey Matter Control AWS EC2 discovery setup documentation for how to configure this with Grey Matter Control.
The Grey Matter Control server uses the AWS SDKs to parse out information about particular EC2 instances and populate the mesh accordingly. Specifically, the Control server will look for deployments into bare metal EC2 instances that take advantage of Instance Tagging to perform service announcement and service discovery.
See the ec2 tags setup documentation for information about the specific format of these tags and how to configure the Grey Matter Control server.
In practice, there are several ways to tag an instance - including via the EC2 Console and using the AWS CLI.