Model/infrastructure/terraform/lambda/_template

Checklist for adding a new Lambda

1. Create the Lambda scaffold

• Copy the template:

  cp -r lambda/_template lambda/<lambda_name>

• Update variables.tf if required

• Ensure the Terraform module accepts:

  • lambda_name
  • stage
  • image_uri

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2. Add infrastructure prerequisites (shared stack)

• Add a new ECR repository in:

  infrastructure/terraform/shared/main.tf

• Apply the shared stack (or let CI apply it on prod)

• Verify the ECR repository exists in AWS

Note:
No Terraform outputs are required for the ECR repo.
The CI pipeline resolves the repository URL dynamically at build time.

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3. Add Docker build configuration

• Create a Dockerfile for the Lambda
• Verify the Dockerfile path and build context
• Add a new image build job in deploy_terraform.yml using _build_image.yml

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4. Wire the Lambda deploy job (CI)

• Add a deploy job using _deploy_lambda.yml
• Pass the following inputs:
  • lambda_name
  • lambda_path
  • stage
  • image_uri (constructed as repo@sha256:digest)
• Ensure the deploy job depends on the image build job

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5. Deploy

• Push changes to GitHub
• CI will:
  1. Build and push the Docker image
  2. Resolve the image digest
  3. Deploy the Lambda using the immutable image_uri

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Notes

• Terraform remote state is not used for image wiring
• Image tags are not used; deployments are digest-based
• By default, the template wires SQS → Lambda
  To change this, update the Terraform in lambda/<lambda_name>
  (e.g. EventBridge, API Gateway, direct invoke)

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Rule of thumb

CI decides what image to deploy.
Terraform only deploys it.