Pulumi vs Terraform: Key Differences and Which IaC Tool to Choose

Pulumi and Terraform are both IaC tools that provision cloud resources from version-controlled files. The core difference is language. Pulumi runs programs in Python, TypeScript, JavaScript, Go, .NET, and Java, plus YAML and HCL. Terraform uses only HCL. Choose Terraform for the largest community and a simple declarative language. Choose Pulumi when software engineers own the infrastructure and want real code, real tests, and built-in secrets handling. OpenTofu is the open-source fork of Terraform. In the 2026 Stack Overflow survey, 18.3% of developers used Terraform and 2.0% used Pulumi. This guide covers Terraform vs Pulumi in 2026, with OpenTofu as a third option.

AppRecode uses Terraform on client projects, and we have not published a Pulumi case. So this comparison rests on the vendors’ own documentation, OpenTofu’s docs, and public survey data. Pulumi’s comparison page is written by Pulumi, so we checked its claims against the Terraform docs.

Both tools describe the cloud resources you want, then create and update them to match. Both keep a record of what they manage, called state, and both support all major clouds.

• Terraform is an infrastructure as code tool created by HashiCorp, which IBM acquired in February 2025. You write HashiCorp Configuration Language (HCL), a domain-specific language built for configuration. Terraform is distributed under the Business Source License 1.1 and has a commercial offering, HCP Terraform (formerly Terraform Cloud), plus Terraform Enterprise.
• Pulumi is an IaC platform where you write programs in general-purpose languages. The Pulumi CLI and SDKs are open source under Apache 2.0, and Pulumi Cloud is the commercial product for managed state, access control, and policy.

The workflow differs in small ways. Teams using Pulumi write a Pulumi program in a language they know, and Pulumi code can call Pulumi packages and Pulumi providers from its registry. Adopting Pulumi means learning stacks and components. Teams using Terraform keep Terraform code in modules, and HCL describes the desired state. Both tools manage cloud infrastructure and track infrastructure state in a backend.

No. They solve the same problem, and they differ in approach. Terraform asks you to describe infrastructure in a purpose-built language. Pulumi lets you describe it in the language your developers already use, with loops and functions, plus classes. Pulumi can also run HCL, and it can reuse Terraform providers and modules, so the two overlap more than the names suggest.

This table compares the two tools. Most rows come from Pulumi’s own comparison page, which is vendor material, and the sections below add detail from the Terraform documentation.

HCL is compact and constrained by design. It has no classes and limited runtime logic, and reuse comes through modules. Many teams like that, because a configuration is easy to read and review.

Pulumi trades that simplicity for power. In a general-purpose language you can use loops and functions, plus classes, and you can test infrastructure with the frameworks you already run. A Pulumi language runtime handles the rest. Pulumi’s unit tests can mock resource calls, so they run without cloud credentials.

Terraform has narrowed the gap on testing. Its built-in terraform test command runs HCL test files against plan or apply results, with optional mock providers.

There is one more point. HashiCorp offered a code-based route called CDK for Terraform, but it announced that CDKTF would sunset and be archived on December 10, 2025. If you wanted real code on top of Terraform, that path is closed, and Pulumi is now the main route to code-first infrastructure.

State management differs most. Terraform stores state in a local file by default. The Terraform documentation says that file is plain text and includes any secret values in your configuration, so many teams use remote state. Remote backends help: HCP Terraform encrypts state at rest, and the S3 backend can too, but encryption depends on the backend you choose.

Terraform has also added ways to keep secrets out of state. Version 1.10 introduced ephemeral values, and version 1.11 added write-only arguments on managed resources. Pulumi says it encrypts secrets in state by default and uses a separate encryption key for each stack, with AWS KMS, Azure Key Vault, Google Cloud KMS, and Vault as options. So the old claim that “Terraform leaves secrets in state” is only partly true today. It depends on your version, your providers, and your backend.

Both have large provider catalogs. Pulumi can adapt any Terraform provider into a Pulumi provider and can use existing Terraform modules directly. It also maintains native providers for Kubernetes and Azure, plus Google Cloud, generated from each cloud provider API schema. Pulumi’s own page admits that Terraform’s longer history means a bigger catalog of community modules and more provider maturity.

Terraform has been distributed under the Business Source License 1.1 since version 1.6, so it is no longer open source in the strict sense. Pulumi’s CLI and SDKs are Apache 2.0. Both companies sell a managed platform, and pricing changes often. Compare Pulumi pricing with HCP Terraform and Terraform Enterprise before you commit. Pulumi Cloud’s free edition includes managed state.

The 2026 Stack Overflow Developer Survey asked developers which infrastructure as code solutions they used. Terraform reached 18.3%, OpenTofu 3.6%, and Pulumi 2.0%. Among people who used them, 45.7% of Terraform users and 61.1% of OpenTofu users said they want to keep using the tool.

These are developer survey results, not job-market data, and respondents are not all infrastructure engineers. They show that Terraform has far more users, and that a smaller tool can still be the right fit for a team.

OpenTofu is the open-source fork of Terraform, maintained under the Linux Foundation and licensed under MPL 2.0. It keeps HCL and the Terraform workflow, so most Terraform skills transfer.

OpenTofu supports state and plan encryption at rest, for local files and for backends. It uses AES-GCM with key providers such as AWS KMS, GCP KMS, Azure Key Vault, and OpenBao. That is a real difference if you want encrypted state without a managed service.

In an OpenTofu vs Terraform decision, the main factors are licensing and governance, because day-to-day use is similar. Try both on a small project before you switch. Many teams that use Terraform and OpenTofu side by side start this way.

Here is how to decide between Pulumi or Terraform. Match your use case to the row, and compare Pulumi with Terraform on your own workload.

Among infrastructure as code tools, these are the main Terraform alternatives. Each one fits a different use case:

• OpenTofu keeps HCL and the Terraform workflow under an open-source license.
• Pulumi moves you to real programming languages.
• AWS CloudFormation and AWS CDK work only on AWS.
• Azure Bicep works only on Azure.
• Crossplane manages cloud resources through Kubernetes.
• Ansible is mainly configuration management, not provisioning.

Pulumi alternatives are the same set seen from the other side: Terraform, OpenTofu, AWS CDK, and Crossplane. Cloud-specific tools can be simpler if you are committed to one cloud. Multi-cloud teams usually pick Terraform, OpenTofu, or Pulumi. Our guide to the wider toolchain puts IaC in context.

They do different jobs. Terraform provisions infrastructure, and Ansible configures what runs on it. Many teams use both. Our comparison guide explains where each fits.

Yes. It is still the most used IaC tool in the 2026 Stack Overflow survey, and it has the largest module library. What has changed is the context: a source-available license, a new owner in IBM, and the end of CDKTF. Those make OpenTofu and Pulumi more credible alternatives than before, and they do not make Terraform obsolete.

Yes. The tools can run side by side. Pulumi can reference an existing Terraform state file, and it can use Terraform providers and modules. It can also run existing HCL and convert it to another language, so using Pulumi does not mean rewriting everything on day one. Pulumi Cloud can serve as a state backend for Terraform and OpenTofu as well.

Moving the other way is harder, because code-based logic does not map neatly to HCL. Plan a pilot, and migrate one stack at a time. Our guides to Terraform import and state handling cover the Terraform side.

1. List your skills. Count who writes HCL and who writes a general-purpose language.
2. Map your cloud provider needs. Check that every provider you need is supported.
3. Check state and secrets, plus policy needs. Decide whether you need encrypted remote state, and where policy runs.
4. Settle licensing and ownership. Decide whether an open-source license matters to you.
5. Run a pilot. Build the same small stack in both tools, and compare review time, test coverage, and how the team feels.

AppRecode’s DevOps consulting company service covers strategy, CI/CD design, and IaC, and it works with existing infrastructure and tools. Our CI/CD consulting and Kubernetes consulting teams build the pipelines and platform layers. Not sure which tool to pick? A DevOps health check shows where your current setup stands.

“I’m extremely satisfied with Apprecode’s DevOps services. Their team was knowledgeable, and professional and gave prompt feedback. I recommend them for any project.” Michael Lazor, CEO of SPSoft

To scope your own IaC program, send a request.

There is no single winner. Terraform has the biggest community, OpenTofu offers the open-source route with the same language, and Pulumi gives you real programming languages. Pick by team skills, licensing needs, and the results of a pilot.

Yes. Pulumi supports HCL as a language, so existing .tf files can run on Pulumi’s engine. A few settings differ: the backend and required version in the terraform block are ignored, because Pulumi manages state itself.

The Pulumi CLI and SDKs are free and open source under Apache 2.0, and Pulumi uses the package manager of your language for reuse. Pulumi Cloud has a free edition with managed state, and paid editions add collaboration, access control, audit logs, and policy management. Check the current plan details on Pulumi’s site.

If your goal is the widest community and module library, start with Terraform. If you are a software engineer who wants to use a language you already know, Pulumi is a reasonable start. Learning either one teaches the core ideas of infrastructure as code.