🔧 Add a Stack

Use this guide when you need to introduce a new CloudFormation stack to stackaroo.yaml.

1. Create the stack entry

Append a block under the stacks list:

stacks:
  - name: payment-app-network
    template: network.yaml
    parameters:
      VpcCidr: "10.0.0.0/16"
      AvailabilityZones:
        - ap-southeast-4a
        - ap-southeast-4b
    tags:
      CostCentre: shared-services
      Tier: shared-network

• name becomes the CloudFormation stack name. Keep it unique per region.
• template resolves relative to templates.directory.
• parameters accept literal values, nested lists, or stack-output references.
• tags override the project defaults for this stack only.

2. Override for specific contexts

Tailor parameters or tags per environment by nesting a contexts block:

  - name: payment-app-service
    template: app.yaml
    parameters:
      DesiredCapacity: "2"
      VpcId:
        type: stack-output
        stack_name: payment-app-network
        output_key: VpcId
    contexts:
      production:
        parameters:
          DesiredCapacity: "6"
        tags:
          CostCentre: prod-payments
          Tier: critical

Rules to remember:

• Literal keys replace the base value (DesiredCapacity increases from 2 to 6 in production).
• Lists replace the entire list—restate every item if only one value changes.
• Tags merge with the base set; reuse the same key to override a value.

3. Keep stacks readable

• Group related stacks (networking, security, application) together.
• Add comments for non-obvious parameter choices.
• Move large inline assets (user data scripts, policy documents) into separate template files or use template helpers.

Once the stack definition is in place, see the dependency and validation guides to wire it into the rest of the project safely.