CloudFormation Conversion [Beta]

February 16, 2026 ยท View on GitHub

Convert CloudFormation templates to diagram-as-code diagrams.

Beta Feature: This functionality is currently in beta. It sometimes works correctly, but we are aware of several known issues. See known issues for current status.

Overview

The --cfn-template option allows you to generate diagrams from CloudFormation templates, providing a visual representation of your infrastructure before deployment.

Two workflows available:

  1. Direct Conversion: Generate diagram directly from CloudFormation template
  2. DAC File Generation: Create editable YAML file for customization

Direct Conversion Workflow

Generate a diagram directly from your CloudFormation template.

Usage

awsdac template.yaml --cfn-template

Output: output.png (default filename)

Custom Output Filename

awsdac template.yaml --cfn-template -o my-architecture.png

Example output:

CloudFormation conversion example

When to Use

  • Quick visualization of CloudFormation resources
  • Initial diagram generation
  • Simple templates with clear resource relationships

Limitations

  • Layout may not be optimal for complex templates
  • Some CloudFormation features not yet supported
  • Resource positioning is automatic and cannot be customized in this mode

DAC File Generation Workflow

Generate an editable YAML file that you can customize before creating the final diagram.

Workflow:

CloudFormation template --[awsdac]--> DAC YAML file --[customize]--> Final diagram

This approach offers greater flexibility by decoupling diagram generation from CloudFormation template structure.

Usage

awsdac template.yaml --cfn-template --dac-file

Outputs:

  • output.yaml - Editable DAC file
  • output.png - Initial diagram

Customization Process

  1. Generate DAC file:

    awsdac template.yaml --cfn-template --dac-file -o custom.yaml

  2. Edit the DAC file (custom.yaml):

    • Adjust resource positioning
    • Add/remove resources
    • Customize titles and labels
    • Modify link connections

  3. Generate final diagram:

    awsdac custom.yaml -o final-diagram.png

When to Use

  • Complex CloudFormation templates
  • Need precise control over diagram layout
  • Want to add custom annotations
  • Generated diagram needs improvement

Known Issues

CloudFormation templates have various dependencies and complex relationships. Some patterns may not work as expected.

Current known issues:

  • Complex nested stacks may not render correctly
  • Some resource dependencies are not automatically detected
  • Custom resources are not supported

Track issues: GitHub Issue Tracker

Report new issues: Your feedback helps improve the tool!

Examples

Example 1: Simple VPC with Subnets

CloudFormation template (vpc-simple.yaml):

Resources:
  MyVPC:
    Type: AWS::EC2::VPC
  PublicSubnet:
    Type: AWS::EC2::Subnet
  PrivateSubnet:
    Type: AWS::EC2::Subnet

Generate diagram:

awsdac vpc-simple.yaml --cfn-template

Example 2: Web Application with ALB

Generate and customize:

# Generate DAC file
awsdac web-app.yaml --cfn-template --dac-file -o web-app-dac.yaml

# Edit web-app-dac.yaml to improve layout

# Generate final diagram
awsdac web-app-dac.yaml -o web-app-final.png