# Terraform vs CloudFormation vs CDK vs Pulumi: Which IaC Tool for AWS?

> Compare Terraform/OpenTofu, AWS CloudFormation, AWS CDK and Pulumi for AWS infrastructure: language, state, multi-cloud, drift, learning curve and when to choose each.

- Source: https://www.itwonderlab.com/terraform-vs-cloudformation/
- Published: 2026-02-03
- Updated: 2026-02-03
- Author: Javier Ruiz Jiménez (https://www.javierruizjimenez.com/)
- Site: IT Wonder Lab (https://www.itwonderlab.com/)

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## Choosing an Infrastructure as Code tool for AWS

All of these tools do the same job: they create and update cloud resources from code ([Infrastructure as Code](https://www.itwonderlab.com/iac/)). They differ in language, how they keep state, and how well they work beyond AWS.

### Quick comparison

| | Terraform / OpenTofu | CloudFormation | AWS CDK | Pulumi |
|---|---|---|---|---|
| Language | HCL (declarative) | JSON or YAML | TypeScript, Python, Java, C#, Go | TypeScript, Python, Go, C#, Java, YAML |
| Clouds | Any, via providers | AWS only | AWS (CDK for Terraform for others) | Any |
| State | State file you manage in a [backend](https://www.itwonderlab.com/terraform-backend/) | Managed by AWS (stacks) | Managed by CloudFormation | Pulumi Cloud or self-managed backend |
| Preview of changes | `plan` | Change sets | `cdk diff` and change sets | `pulumi preview` |
| Rollback on failure | No automatic rollback, you fix and re-apply | Automatic rollback | Same as CloudFormation | No automatic rollback |
| Drift detection | `plan` | Drift detection feature | Same as CloudFormation | `refresh` |
| New AWS features | Provider release, usually days to weeks | Often on day one | Day one at L1 level, later at higher levels | Based on Terraform providers or native |
| License | OpenTofu MPL 2.0, Terraform BSL | Proprietary service | Apache 2.0 | Apache 2.0 |
| Cost | Free tool, optional platforms | Free | Free | Free tool, paid cloud features |

### Terraform and OpenTofu

**Strengths:** a huge provider ecosystem (AWS, Azure, GCP, Kubernetes, Cloudflare, Datadog, GitHub), one language for everything, a large community, and a clear `plan`. Good for teams that use more than one platform or service. See [Terraform vs OpenTofu](https://www.itwonderlab.com/terraform-vs-opentofu/).

**Weaknesses:** you operate the state, and there is no automatic rollback. HCL is limited when you need complex logic.

### CloudFormation

**Strengths:** native to AWS, state and locking managed for you, rollbacks, deep integration with [AWS Organizations StackSets](https://www.itwonderlab.com/aws-organizations/), Service Catalog and [Control Tower](https://www.itwonderlab.com/aws-control-tower/), and support for new services early. No extra tool or state bucket. See [CloudFormation](https://www.itwonderlab.com/aws-cloudformation/).

**Weaknesses:** verbose YAML or JSON, AWS only, and stack operations can be slow and sometimes get stuck in a failed state.

### AWS CDK

**Strengths:** write infrastructure in a general-purpose language with loops, classes and tests, and get high-level constructs that create sensible defaults (an entire VPC or an ECS service in a few lines). It synthesizes CloudFormation templates.

**Weaknesses:** AWS only, you still debug CloudFormation underneath, and the abstraction can hide what is created. Developers like it, platform teams are sometimes more cautious.

### Pulumi

**Strengths:** real programming languages across clouds, with a state model like Terraform. A good fit when developers own the infrastructure and want to share code with applications.

**Weaknesses:** a smaller ecosystem and community than Terraform, and a language runtime in your pipeline.

### How to choose

| Situation | Suggestion |
|---|---|
| Multi-cloud or many SaaS providers | Terraform or OpenTofu |
| AWS only and you want the least tooling | CloudFormation |
| AWS only and developers prefer code | CDK |
| You need an open-source license | OpenTofu, CDK or Pulumi |
| Large Terraform skill base and hiring market | Terraform or OpenTofu |
| Complex logic and unit testing with a normal language | CDK or Pulumi |

### Combining tools

They are not exclusive. A common setup: **Terraform for the cloud foundation** (accounts, network, IAM) and **CDK or CloudFormation for applications**, or Terraform managing CloudFormation stacks with `aws_cloudformation_stack` during a migration. Choose one per layer and avoid two tools managing the same resource.

### Learning path

If you start from scratch and expect to work in more than one cloud, learn HCL: it is the most requested skill. Follow the [AWS with Terraform series](https://www.itwonderlab.com/tutorials/aws/), the [Terraform cheat sheet](https://www.itwonderlab.com/terraform-cheat-sheet/) and the [best practices](https://www.itwonderlab.com/terraform-best-practices/). For job preparation see the [interview questions](https://www.itwonderlab.com/terraform-interview-questions/).

To move an existing setup, see [import](https://www.itwonderlab.com/terraform-import-moved-removed/) (adopt resources created by CloudFormation or by hand) and [migrating to OpenTofu](https://www.itwonderlab.com/terraform-to-opentofu/).