FR-IMG-003 — Immutable Infrastructure Workflows

Go to Crucible Image Management Requirements

Crucible SHALL apply changes to deployed images by replacing the images rather than modifying them in place.

This requirement derives from:

• Crucible System Requirements Specification, Version 1.1 Draft, Functional Requirements, FR-IMG-003

The Original Requirement states:

The system shall support immutable infrastructure workflows.[C1]

FR-IMG-003:

• Replaces The system with the defined system name Crucible
• Changes shall to the established uppercase normative form SHALL
• Replaces the weak verb support with the observable behavior apply
• Expresses immutable image management as replacement rather than in-place modification

An immutable infrastructure workflow applies a change by replacing a deployed image with a newly built image rather than modifying the deployed image in place.

Replacement preserves the relationship between a deployed subject and the image Artifact from which the subject was created.

This approach reduces configuration drift and supports repeatable deployment of Machine Images and Container Images.

This requirement applies to:

• Crucible
• Machine Images
• Container Images
• Deployed images
• Image replacement operations

Verification confirms that:

1. A change to a tested deployed image produces a replacement image
2. Crucible replaces the tested deployed image with the replacement image
3. Crucible does not apply the tested change by modifying the deployed image in place
4. The replacement image can be identified as distinct from the image it replaces

The following pages reference this requirement:

Implemented and Verified

Review and approve FR-IMG-003 as a leaf requirement.

Determine whether Immutable Infrastructure Workflow requires a controlled definition in the shared Terms and Definitions corpus.

Determine whether separate requirements define replacement failure and recovery behavior.

This requirement page retains the stable requirement identifier FR-IMG-003.

This page is a leaf requirement page and omits a trailing :start from its namespace.

The Statement preserves the approved source intent by requiring image changes to use replacement rather than in-place modification.

Do not add image building, signing, verification, promotion, deployment validation, rollback, or recovery obligations to the Statement unless the controlling requirement changes through an approved requirements process.

To reference this requirement Statement from another wiki page, insert:

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