cloudformation-best-practices

sickn33/agentic-awesome-skills · plugins/agentic-awesome-skills-claude/skills/cloudformation-best-practices/SKILL.md

CloudFormation template optimization, nested stacks, drift detection, and production-ready patterns. Use when writing or reviewing CF templates.

No license★ 45496⑂ 6664commit 5cf4dfe

Install skillView source on GitHub

What this skill does

You are an expert in AWS CloudFormation specializing in template optimization, stack architecture, and production-grade infrastructure deployment.

Use this skill when

Writing or reviewing CloudFormation templates (YAML/JSON)
Optimizing existing templates for maintainability and cost
Designing nested or cross-stack architectures
Troubleshooting stack creation/update failures and drift

Do not use this skill when

The user prefers CDK or Terraform over raw CloudFormation
The task is application code, not infrastructure

Instructions

Use YAML over JSON for readability.
Parameterize environment-specific values; use Mappings for static lookups.
Apply DeletionPolicy: Retain on stateful resources (RDS, S3, DynamoDB).
Use Conditions to support multi-environment templates.
Validate templates with aws cloudformation validate-template before deployment.
Prefer !Sub over !Join for string interpolation.

Examples

Example 1: Parameterized VPC Template

AWSTemplateFormatVersion: "2010-09-09"
Description: Production VPC with public and private subnets

Parameters:
  Environment:
    Type: String
    AllowedValues: [dev, staging, prod]
  VpcCidr:
    Type: String
    Default: "10.0.0.0/16"

Conditions:
  IsProd: !Equals [!Ref Environment, prod]

Resources:
  VPC:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: !Ref VpcCidr
      EnableDnsSupport: true
      EnableDnsHostnames: true
      Tags:
        - Key: Name
          Value: !Sub "${Environment}-vpc"

Outputs:
  VpcId:
    Value: !Ref VPC
    Export:
      Name: !Sub "${Environment}-VpcId"

Best Practices

✅ Do: Use Outputs with Export for cross-stack references
✅ Do: Add DeletionPolicy and UpdateReplacePolicy on stateful resources
✅ Do: Use cfn-lint and cfn-nag in CI pipelines
❌ Don't: Hardcode ARNs or account IDs — use !Sub with pseudo parameters
❌ Don't: Put all resources in a single monolithic template

Troubleshooting

Problem: Stack stuck in UPDATE_ROLLBACK_FAILED Solution: Use continue-update-rollback with --resources-to-skip for the failing resource, then fix the root cause.

Limitations

Use this skill only when the task clearly matches the scope described above.
Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.

Installation

Copy a source-pinned command for your client. You run it yourself.

Destination: .claude/skills/cloudformation-best-practices · pinned to the source commit

# Run from your project root
git clone https://github.com/sickn33/agentic-awesome-skills.git .skillboard-tmp
git -C .skillboard-tmp checkout 5cf4dfeb13ea966daa1e117897689cd7991e3f44
mkdir -p ".claude/skills"
cp -r ".skillboard-tmp/plugins/agentic-awesome-skills-claude/skills/cloudformation-best-practices" ".claude/skills/"
rm -rf .skillboard-tmp

Review the source before running. This copies files into your project; it is not a one-click install and does not verify runtime safety.

New here? Step-by-step setup – from installing the agent to using the skill

Operating systemAgentI already use Claude Code

1
Install Git
Install Git with your package manager (Debian/Ubuntu shown; use dnf/pacman on others). Official download.
```
sudo apt update && sudo apt install -y git
```
2
Install Claude Code
Requires Node.js 18+. Install the CLI globally: Official docs. (command-line tool)
```
npm install -g @anthropic-ai/claude-code
```

Get the skill, pinned to its exact version

Open a terminal and run these steps (they clone the source, check out the exact commit, and copy the skill into place):

# Run from your project root
git clone https://github.com/sickn33/agentic-awesome-skills.git .skillboard-tmp
git -C .skillboard-tmp checkout 5cf4dfeb13ea966daa1e117897689cd7991e3f44
mkdir -p ".claude/skills"
cp -r ".skillboard-tmp/plugins/agentic-awesome-skills-claude/skills/cloudformation-best-practices" ".claude/skills/"
rm -rf .skillboard-tmp

Destination: .claude/skills/cloudformation-best-practices

4
Use it in Claude Code
Open Claude Code in your project. It reads skills from the folder above, so cloudformation-best-practices is now available. Always review the source before using it – static checks cannot prove runtime safety.

Security & Audits

Scanner static-checks@0.1.0 · commit 5cf4dfeb13ea. Static checks cannot prove runtime safety – review the source and the exact diff before installing. How checks work.

No static rules matched. This is not a safety guarantee.

cloudformation-best-practices

sickn33/agentic-awesome-skills · plugins/agentic-awesome-skills-claude/skills/cloudformation-best-practices/SKILL.md

CloudFormation template optimization, nested stacks, drift detection, and production-ready patterns. Use when writing or reviewing CF templates.

No license★ 45496⑂ 6664commit 5cf4dfe

Install skillView source on GitHub

What this skill does

You are an expert in AWS CloudFormation specializing in template optimization, stack architecture, and production-grade infrastructure deployment.

Use this skill when

Writing or reviewing CloudFormation templates (YAML/JSON)
Optimizing existing templates for maintainability and cost
Designing nested or cross-stack architectures
Troubleshooting stack creation/update failures and drift

Do not use this skill when

The user prefers CDK or Terraform over raw CloudFormation
The task is application code, not infrastructure

Instructions

Use YAML over JSON for readability.
Parameterize environment-specific values; use Mappings for static lookups.
Apply DeletionPolicy: Retain on stateful resources (RDS, S3, DynamoDB).
Use Conditions to support multi-environment templates.
Validate templates with aws cloudformation validate-template before deployment.
Prefer !Sub over !Join for string interpolation.

Examples

Example 1: Parameterized VPC Template

AWSTemplateFormatVersion: "2010-09-09"
Description: Production VPC with public and private subnets

Parameters:
  Environment:
    Type: String
    AllowedValues: [dev, staging, prod]
  VpcCidr:
    Type: String
    Default: "10.0.0.0/16"

Conditions:
  IsProd: !Equals [!Ref Environment, prod]

Resources:
  VPC:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: !Ref VpcCidr
      EnableDnsSupport: true
      EnableDnsHostnames: true
      Tags:
        - Key: Name
          Value: !Sub "${Environment}-vpc"

Outputs:
  VpcId:
    Value: !Ref VPC
    Export:
      Name: !Sub "${Environment}-VpcId"

Best Practices

✅ Do: Use Outputs with Export for cross-stack references
✅ Do: Add DeletionPolicy and UpdateReplacePolicy on stateful resources
✅ Do: Use cfn-lint and cfn-nag in CI pipelines
❌ Don't: Hardcode ARNs or account IDs — use !Sub with pseudo parameters
❌ Don't: Put all resources in a single monolithic template

Troubleshooting

Problem: Stack stuck in UPDATE_ROLLBACK_FAILED Solution: Use continue-update-rollback with --resources-to-skip for the failing resource, then fix the root cause.

Limitations

Use this skill only when the task clearly matches the scope described above.
Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.

Installation

Copy a source-pinned command for your client. You run it yourself.

Destination: .claude/skills/cloudformation-best-practices · pinned to the source commit

# Run from your project root
git clone https://github.com/sickn33/agentic-awesome-skills.git .skillboard-tmp
git -C .skillboard-tmp checkout 5cf4dfeb13ea966daa1e117897689cd7991e3f44
mkdir -p ".claude/skills"
cp -r ".skillboard-tmp/plugins/agentic-awesome-skills-claude/skills/cloudformation-best-practices" ".claude/skills/"
rm -rf .skillboard-tmp

Review the source before running. This copies files into your project; it is not a one-click install and does not verify runtime safety.

New here? Step-by-step setup – from installing the agent to using the skill

Operating systemAgentI already use Claude Code

1
Install Git
Install Git with your package manager (Debian/Ubuntu shown; use dnf/pacman on others). Official download.
```
sudo apt update && sudo apt install -y git
```
2
Install Claude Code
Requires Node.js 18+. Install the CLI globally: Official docs. (command-line tool)
```
npm install -g @anthropic-ai/claude-code
```

Get the skill, pinned to its exact version

Open a terminal and run these steps (they clone the source, check out the exact commit, and copy the skill into place):

# Run from your project root
git clone https://github.com/sickn33/agentic-awesome-skills.git .skillboard-tmp
git -C .skillboard-tmp checkout 5cf4dfeb13ea966daa1e117897689cd7991e3f44
mkdir -p ".claude/skills"
cp -r ".skillboard-tmp/plugins/agentic-awesome-skills-claude/skills/cloudformation-best-practices" ".claude/skills/"
rm -rf .skillboard-tmp

Destination: .claude/skills/cloudformation-best-practices

4
Use it in Claude Code
Open Claude Code in your project. It reads skills from the folder above, so cloudformation-best-practices is now available. Always review the source before using it – static checks cannot prove runtime safety.

Security & Audits

Scanner static-checks@0.1.0 · commit 5cf4dfeb13ea. Static checks cannot prove runtime safety – review the source and the exact diff before installing. How checks work.

No static rules matched. This is not a safety guarantee.

cloudformation-best-practices

What this skill does

Use this skill when

Do not use this skill when

Instructions

Examples

Example 1: Parameterized VPC Template

Best Practices

Troubleshooting

Limitations

Installation

Install Git

Install Claude Code

Get the skill, pinned to its exact version

Use it in Claude Code

Security & Audits

cloudformation-best-practices

What this skill does

Use this skill when

Do not use this skill when

Instructions

Examples

Example 1: Parameterized VPC Template

Best Practices

Troubleshooting

Limitations

Installation

Install Git

Install Claude Code

Get the skill, pinned to its exact version

Use it in Claude Code

Security & Audits