K8s Deployment Diff Tool

Kubernetes Deployment manifests contain dozens of nested fields: replica counts, container images, resource requests and limits, environment variables, volume mounts, probes, and strategy settings. When a deployment is updated — especially via CI/CD automation or Helm — quickly understanding what changed is essential for safe rollouts and incident response.

This tool compares two Deployment YAML documents and presents the diff as a structured list of field changes. Each changed field is shown with its path (e.g. spec.replicas, spec.template.spec.containers[0].image, spec.template.spec.containers[0].resources.requests.cpu), the old value in red, and the new value in green. Added fields appear with a + prefix and removed fields with a − prefix.

Because the diff is semantic rather than textual, trivial formatting differences — different indentation, reordered map keys, added comments — do not appear in the output. Only changes that affect the actual deployed configuration are shown. Paste the output of kubectl get deployment <name> -o yaml before and after a change to immediately see what the cluster update will apply.