Under Atmos

What you change

1. components.terraform.command: choudoufu in atmos.yaml.
2. A live block in each component’s terraform block, naming its estate and the record store:

terraform {
  live {
    estate = "app"

    record_store "s3" {
      bucket = "my-records-bucket"
    }
  }
}

The stack and its vars stay as they are, with !terraform.output and !terraform.state between components. Workspaces and the generated backend.tf.json stay too. choudoufu accepts the workspace and init -reconfigure with a warning each. For a component that already owns resources, follow Migrate before the first apply.

If you keep plans in Atmos’s planfile store, set planfiles.verify: warn and planfiles.required: true. Atmos counts a value that was known after apply in the stored plan, and is known now, as drift, so a stored plan that reads a new ID cannot pass its check. choudoufu does the refusing instead.

What you get

	Stock Atmos	On the live backend
One plan covers every component	No, one per component	Yes
A changed value reaches the components that read it	No, !terraform.output reads the last applied outputs	Yes
A new ID reaches the components that read it	Only as a default or a mock	Yes, as known after apply
The approved plan is what applies	The planfile store, which counts a newly known value as drift	Yes, and choudoufu refuses any other change
Applies	One per component	One per component

The workflow

The pull request plans the components the change reaches, and the merge deploys them from the stored plans:

atmos terraform plan --affected --include-dependents --ci
atmos terraform deploy --affected --include-dependents --ci

The deploy applies each component in turn from a fresh plan. choudoufu refuses, with exit status 3, a fresh plan that differs from the stored one in anything but values that were known after apply.

Limits

• --affected plans what Atmos names, so --include-dependents is needed for the components that read a changed one.
• Stored plans are keyed by commit. Merge fast-forward only, or rebase and plan again before the merge.
• A var that is !terraform.output or !terraform.state with an output name or a simple path is taken from the joint plan. A yq expression with //, !store, a template calling atmos.Component, or a function nested in a list or map keeps Atmos’s value.

A worked example is examples/demo-atmos.