GitOps is a way of implementing Continuous Deployment for cloud native applications. Based on Git and Continuous Deployment tools, GitOps provides a declarative way to store the desired state of your infrastructure and automated processes to realize the desired state in your production environment.
For example, to deploy a new application you update the repository, and the automated processes perform the actual deployment steps.
When used in operator mode, Service Mesh Manager works flawlessly with GitOps solutions such as Argo CD, and can be used to declaratively manage your service mesh. For a detailed tutorial on setting up Argo CD with Service Mesh Manager, see Install SMM - GitOps - single cluster.