Static Validation Patterns: Infrastructure Validation Without a Cluster

Static Validation Patterns#

Static validation catches infrastructure errors before anything is deployed. No cluster needed, no cloud credentials needed, no cost incurred. These tools analyze configuration files – Helm charts, Kubernetes manifests, Terraform modules, Kustomize overlays – and report problems that would cause failures at deploy time.

Static validation does not replace integration testing. It cannot verify that a service starts successfully, that a pod can pull its image, or that a database accepts connections. What it catches are structural errors: malformed YAML, invalid API versions, missing required fields, policy violations, deprecated resources, and misconfigured values. In practice, this covers roughly 40% of infrastructure issues – the ones that are cheapest to find and cheapest to fix.

Testing Infrastructure Code: The Validation Pyramid from Lint to Integration

Testing Infrastructure Code#

Infrastructure code has a unique testing challenge: the thing you are testing is expensive to instantiate. You cannot spin up a VPC, an RDS instance, and an EKS cluster for every pull request and tear it down 5 minutes later without significant cost and time. But you also cannot ship untested infrastructure changes to production without risk.

The solution is the same as in software engineering: a testing pyramid. Fast, cheap tests at the bottom catch most errors. Slower, expensive tests at the top catch the rest. The key is knowing what to test at which level.