Terraform vs CloudFormation vs Pulumi - Visual Side-by-Side Comparison

Process Flow - Terraform vs CloudFormation vs Pulumi

Start: Choose IaC Tool

↓

Deploy Infrastructure

↓

Manage State & Updates

↓

Infrastructure Ready

The flow shows choosing between Terraform, CloudFormation, or Pulumi, then deploying and managing infrastructure.

Execution Sample

Terraform

terraform {
  required_providers {
    aws = { source = "hashicorp/aws" version = "~> 4.0" }
  }
}
resource "aws_s3_bucket" "example" {
  bucket = "my-unique-bucket-12345"
}

This Terraform code creates an AWS S3 bucket named 'my-unique-bucket-12345'.

Process Table

Step	Action	Tool Behavior	Result
1	Initialize Terraform	Reads config, downloads AWS provider	Ready to plan
2	terraform plan	Compares desired state with current	Shows bucket to create
3	terraform apply	Creates S3 bucket in AWS	Bucket 'my-unique-bucket-12345' created
4	CloudFormation equivalent	Uses JSON/YAML template	Creates same bucket in AWS
5	Pulumi equivalent	Uses code in Python/JS/etc.	Creates same bucket in AWS
6	Manage updates	Terraform tracks state file	Updates or deletes resources as needed
7	Exit	Infrastructure deployed and managed	Ready for use

💡 Infrastructure is deployed and managed by the chosen tool.

Status Tracker

Variable	Start	After Init	After Plan	After Apply	Final
terraform_state	empty	initialized	planned (bucket to create)	applied (bucket created)	current state with bucket
aws_s3_bucket.example	none	defined in config	planned for creation	created in AWS	exists and ready

Key Moments - 3 Insights

Why does Terraform use a state file while CloudFormation does not?

Terraform keeps a local or remote state file to track resources across clouds, while CloudFormation manages state internally within AWS. See execution_table rows 6 and 4.

Can Pulumi use the same languages as Terraform?

No, Pulumi uses general-purpose languages like Python or JavaScript, while Terraform uses its own HCL language. See concept_flow and execution_table rows 5 and 1.

Why choose CloudFormation over Terraform?

CloudFormation is AWS-native and may have faster support for new AWS features. Terraform supports multiple clouds but may lag. See concept_flow and execution_table rows 4 and 1.

Visual Quiz - 3 Questions

Look at the execution_table, at which step is the S3 bucket actually created in AWS?

A Step 3

B Step 4

C Step 2

D Step 6

💡 Hint

Check the 'Result' column for when the bucket is created.

According to variable_tracker, what is the state of 'terraform_state' after 'terraform plan'?

A empty

B initialized

C planned (bucket to create)

D applied (bucket created)

💡 Hint

Look at the 'After Plan' column for 'terraform_state'.

If you want to use Python code to define infrastructure, which tool from concept_flow would you pick?

A CloudFormation

B Pulumi

C Terraform

D None of these

💡 Hint

See the 'Pulumi' box in concept_flow mentioning general languages.

Concept Snapshot

Terraform, CloudFormation, and Pulumi are tools to create cloud infrastructure.
Terraform uses HCL and supports many clouds.
CloudFormation is AWS-only and uses JSON/YAML.
Pulumi uses real programming languages and supports many clouds.
All deploy resources and manage updates differently.

Full Transcript

This visual execution compares Terraform, CloudFormation, and Pulumi. It starts with choosing a tool, then shows Terraform code creating an AWS S3 bucket. The execution table traces initialization, planning, applying, and managing infrastructure. Variable tracking shows how Terraform state and resource definitions change step-by-step. Key moments clarify differences in state management, language use, and cloud support. The quiz tests understanding of when resources are created, state changes, and tool language options. The snapshot summarizes key points for quick recall.

Practice

1. Which infrastructure as code tool is designed to work only with AWS and uses JSON or YAML for its templates?

easy

A. CloudFormation

B. Terraform

C. Pulumi

D. Ansible

Solution

1. Step 1: Identify AWS-only tool

   CloudFormation is the only tool among the options that works exclusively with AWS.

2. Step 2: Check template language

   CloudFormation uses JSON or YAML for its templates, unlike Terraform (HCL) or Pulumi (programming languages).

3. Final Answer:

   CloudFormation -> Option A

4. Quick Check:

   AWS-only + JSON/YAML = CloudFormation [OK]

Hint: AWS-only and JSON/YAML means CloudFormation [OK]

Common Mistakes:

• Confusing Terraform as AWS-only
• Thinking Pulumi uses JSON/YAML
• Selecting Ansible which is not IaC focused

2. Which of the following is the correct way to describe Pulumi's approach to infrastructure as code?

easy

A. Uses general-purpose programming languages like JavaScript or Python

B. Uses JSON or YAML templates tightly integrated with AWS

C. Uses shell scripts for provisioning

D. Uses a domain-specific language called HCL

Solution

1. Step 1: Identify Pulumi's language style

   Pulumi uses real programming languages such as JavaScript, Python, Go, or C# for defining infrastructure.

2. Step 2: Eliminate other options

   HCL is Terraform's language, JSON/YAML with AWS is CloudFormation, and shell scripts are not Pulumi's approach.

3. Final Answer:

   Uses general-purpose programming languages like JavaScript or Python -> Option A

4. Quick Check:

   Pulumi = real programming languages [OK]

Hint: Pulumi uses real programming languages, not templates [OK]

Common Mistakes:

• Confusing Pulumi with Terraform's HCL
• Thinking Pulumi uses JSON/YAML
• Assuming Pulumi uses shell scripts

3. Given the following statements, which tool supports multiple cloud providers and uses a simple declarative language called HCL?

1. Supports AWS, Azure, GCP
2. Uses JSON or YAML
3. Uses HCL
4. Uses programming languages like TypeScript

medium

A. Chef

B. Pulumi

C. CloudFormation

D. Terraform

Solution

1. Step 1: Match multi-cloud support

   Terraform supports multiple clouds like AWS, Azure, and GCP.

2. Step 2: Match language used

   Terraform uses HCL, a simple declarative language. JSON/YAML is CloudFormation, programming languages like TypeScript is Pulumi.

3. Final Answer:

   Terraform -> Option D

4. Quick Check:

   Multi-cloud + HCL = Terraform [OK]

Hint: Multi-cloud + HCL means Terraform [OK]

Common Mistakes:

• Choosing Pulumi for HCL language
• Selecting CloudFormation for multi-cloud
• Confusing Chef with IaC tools

4. You wrote a Pulumi program in Python but it fails to deploy because it uses AWS-specific resource names not supported by Azure. What is the main error here?

medium

A. Terraform should be used instead of Pulumi for AWS

B. Pulumi does not support Python as a language

C. Using AWS resource names in a multi-cloud Pulumi program without adjusting for Azure

D. CloudFormation templates are required for Azure deployments

Solution

1. Step 1: Identify the cause of failure

   The Pulumi program uses AWS resource names but tries to deploy on Azure, causing incompatibility.

2. Step 2: Understand Pulumi's multi-cloud nature

   Pulumi supports multiple clouds but resource names and APIs differ per cloud and must be adjusted accordingly.

3. Final Answer:

   Using AWS resource names in a multi-cloud Pulumi program without adjusting for Azure -> Option C

4. Quick Check:

   Cloud-specific resource names must match target cloud [OK]

Hint: Match resource names to target cloud in Pulumi [OK]

Common Mistakes:

• Thinking Pulumi can't use Python
• Believing Terraform is required for AWS
• Assuming CloudFormation works on Azure

5. You want to manage infrastructure across AWS and Azure using a single tool. You prefer writing code in TypeScript and want to reuse existing programming skills. Which tool should you choose and why?

hard

A. CloudFormation, because it is tightly integrated with AWS

B. Pulumi, because it supports multiple clouds and uses real programming languages like TypeScript

C. Terraform, because it supports multiple clouds and uses HCL

D. Ansible, because it uses YAML for automation

Solution

1. Step 1: Identify multi-cloud support with TypeScript

   Pulumi supports multiple clouds and allows writing infrastructure code in TypeScript, matching the requirement.

2. Step 2: Compare other tools

   Terraform supports multi-cloud but uses HCL, not TypeScript. CloudFormation is AWS-only. Ansible is for automation, not primarily IaC with TypeScript.

3. Final Answer:

   Pulumi, because it supports multiple clouds and uses real programming languages like TypeScript -> Option B

4. Quick Check:

   Multi-cloud + TypeScript = Pulumi [OK]

Hint: Multi-cloud + TypeScript means Pulumi [OK]

Common Mistakes:

• Choosing Terraform for TypeScript support
• Selecting CloudFormation for multi-cloud
• Confusing Ansible with IaC tools