Softwr

Cloud · head to head

Terragrunt vs Kustomize

Terragrunt logo

Terragrunt

Cloud

The Open Source IaC Orchestrator Platform Teams Trust

From
Free
Rated
-
Kustomize logo

Kustomize

Cloud

Template-free customisation of Kubernetes YAML

From
Free
Rated
-

The short version

  • Each has a real cost: Terragrunt additional complexity layer on top of Terraform; Kustomize no packaging or distribution story, which is exactly what Helm charts provide
  • They diverge on capability: Terragrunt covers Infrastructure orchestration, Kustomize covers Overlay patching.

Where they differ

Only the attributes on which Terragrunt and Kustomize actually diverge.

Attributes where Terragrunt and Kustomize differ
AttributeTerragruntKustomize
Pricing modelUnknownOpen source, no licence fee
PlatformsAWS, Azure, GCPKubernetes, Linux, macOS, Windows

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated), category (Cloud).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Terragrunt

  • Infrastructure orchestration
  • Run Queue
  • DRY configuration
  • Automated hooks
  • Infrastructure catalog
  • Least-privilege access

Only in Kustomize

  • Overlay patching
  • No templating language
  • Built into kubectl
  • Generators

What people use each for

The jobs each tool is most often brought in to do.

Terragrunt

  • Organizing Terraform code across multiple environmentsnot Kustomize
  • Automating infrastructure deployment workflowsnot Kustomize
  • Implementing infrastructure as code templates for developer self-servicenot Kustomize

Kustomize

  • Managing dev, staging and production variants of the same manifestsnot Terragrunt
  • Keeping manifests readable and directly applyable rather than templatednot Terragrunt
  • Patching third-party manifests without forking themnot Terragrunt

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Terragrunt

  • Additional complexity layer on top of Terraform
  • Requires understanding of Terraform concepts
  • Paid tier pricing not clearly published

Kustomize

  • No packaging or distribution story, which is exactly what Helm charts provide
  • Deeply nested overlays become hard to follow, and reasoning about the final output requires building it
  • No release lifecycle: nothing tracks what is installed or supports rollback the way Helm does
  • Patch syntax is fiddly for anything beyond simple field replacement

Pricing, plan by plan

Terragrunt

Free
  • Open SourceFree
    • Terragrunt CLI - completely free
    • Community support
  • Terragrunt Scale FreeFree
    • Free CI/CD pipeline
    • Unlimited runs and resources
    • For up to 25 infrastructure units
  • Terragrunt Scale Paid$undefined/custom
    • Volume pricing for more than 25 infrastructure units
    • Enterprise support

Kustomize

Free
  • KustomizeFree
    • Full functionality
    • No usage limits
    • Community support

Which should you pick?

Choose Terragrunt if

  • You need infrastructure orchestration.
  • You want to start without paying.
  • You work on AWS, Azure, GCP.
  • You also want run queue.

Choose Kustomize if

  • You need overlay patching.
  • You want to start without paying.
  • You work on Kubernetes, Linux, macOS, Windows.
  • You also want no templating language.

Questions people ask

Is Terragrunt or Kustomize better?
Neither clearly leads. Terragrunt starts at Free and Kustomize at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Terragrunt or Kustomize?
Terragrunt starts at Free and Kustomize at Free.
Does Terragrunt or Kustomize run on more platforms?
Terragrunt runs on AWS, Azure, GCP. Kustomize runs on Kubernetes, Linux, macOS, Windows.
Can I use Terragrunt for free?
Both have a free tier, so you can try either at no cost before committing.
What is Terragrunt best used for?
Terragrunt is most often used for organizing terraform code across multiple environments, automating infrastructure deployment workflows, implementing infrastructure as code templates for developer self-service. Of those, organizing terraform code across multiple environments and automating infrastructure deployment workflows are not what Kustomize is typically brought in for.
What can Terragrunt do that Kustomize cannot?
Terragrunt covers Infrastructure orchestration, Run Queue, DRY configuration, Automated hooks. Kustomize covers Overlay patching, No templating language, Built into kubectl, Generators.

Answered from the vendors’ own pages

Terragrunt: Is Terragrunt free?

Yes, the Terragrunt CLI is completely free and open source. Terragrunt Scale offers a free tier for up to 25 infrastructure units.

Source
Kustomize: Is Kustomize free?

Yes, open source and part of the Kubernetes project.

Terragrunt: What is the difference between Terragrunt and Terraform?

Terragrunt is an orchestration layer on top of Terraform that handles state management, DRY principles, and deployment automation without replacing Terraform itself.

Source
Kustomize: Kustomize or Helm?

Kustomize patches plain YAML and keeps bases readable; Helm templates and packages applications with a release lifecycle. Many teams use both — Helm to install third-party charts, Kustomize to patch them.

Kustomize: Do I need to install Kustomize?

No. It is built into kubectl, available through kubectl apply -k.

Share

Related pages

Other head to heads