Argo CD is an open-source GitOps continuous delivery tool. It monitors your cluster and your declaratively-defined infrastructure stored in a Git repository and resolves differences between the two — effectively automating an application deployment.

What is Argo CD?

At its very simplest, Argo CD is an open-source GitOps continuous delivery tool. It monitors your cluster and your declaratively-defined infrastructure stored in a Git repository and resolves differences between the two — effectively automating an application deployment. 

You may have also heard of it as a Kubernetes controller. Kubernetes helped change how infrastructure is managed, but it also added complexity for developers and system administrators by introducing new concepts like kubernetes manifests, kubernetes resources, and other various Kuberentes specific concepts. As the GitOps movement starts to walk back some of that complexity and abstract it under a layer of automation, Argo CD (“CD” of course being shorthand for “continuous delivery”) is one of the primary tools that makes this automation possible. 

Without Argo CD, GitOps remains “ClickOps.” Your CI/CD tool may be able to roll out infrastructure changes, but it can’t monitor diffs, and thus infrastructure remains mostly manual.

What Does Argo CD Do?

Argo CD is a declarative, GitOps continuous delivery tool built by the team at the financial software giant Intuit. After moving to the public cloud, having to manage containerization tools and infrastructure interfered with Intuit’s goal to realize the maximum benefits of the cloud. The Intuit team developed Argo CD to achieve maximum release speed and velocity gains. They wanted to apply a pane of automation that would eliminate some of that manual work, so they created the controller — Argo CD — and they open-sourced it. 

Why Argo CD?

As a GitOps continuous delivery tool, Argo CD continuously monitors your running infrastructure (the actual state) to compare it to declaratively-defined code (the desired state or target state) to determine whether they are out of sync, which helps to remediate configuration drift. 

Argo CD automatically deploys new configurations and new version code to the target environment. Depending on how you’ve configured Argo CD to work, it’ll either notify you that things are out of sync after a new git commit, or take action. If you’ve set it up to automatically enforce changes, it’ll overwrite the production configuration with what’s stored in your immutable, versioned Git repository. The tool is great for complex application rollouts.

Find out more here.