5.1 Select and Compose Baselines

Go to 5. Operational Concept

Baseline Composition selects identified and version-controlled Baselines and makes their content available within a controlled workspace for the selected Operational Lifecycle activity.

A composition can include:

• Application source
• One or more Image Layers
• One or more Infrastructure Baselines
• A combination of application source, Image Layers, and Infrastructure Baselines

Application source is not required for every composition. A composition containing only Image Layers, Infrastructure Baselines, or both remains valid when those inputs satisfy the selected lifecycle activity.

Baseline selection identifies the Baselines needed to produce the intended result.

The selection identifies:

• Each Baseline
• The selected Baseline revision
• The Baseline source location
• The role of the Baseline in the composition
• The approval status required for its use
• The selected lifecycle activity
• Any applicable Platform Specific Parameters

Crucible uses the identified revision rather than an unspecified or changing repository state. This allows the composition to be reproduced and related to the artifacts, deployments, assessments, and records produced from it.

Crucible places or makes the selected inputs available within a controlled workspace.

The workspace provides the execution context in which Crucible can locate and use:

• Application source, when included
• Selected Image Layers
• Selected Infrastructure Baselines
• Applicable Crucible Descriptions
• Required configuration and parameters
• Inputs required by the selected lifecycle activity

The workspace can contain inputs retrieved from separate repositories. Co-location within the workspace does not merge their identities, histories, or governance.

Each selected Baseline remains independently identifiable and version controlled.

Image Layers describe reusable content and activities applied during image construction and hardening.

A composition can select one or more Image Layers according to the intended image, operating system, security criteria, and applicable lifecycle activity.

The selected Image Layers become controlled inputs to the image-construction activity described in 5.2 Construct Images.

Infrastructure Baselines describe reusable deployment content and lifecycle activities associated with an Infrastructure Environment.

An Infrastructure Baseline can include content used before, during, or after deployment. The applicable requirement and Baseline content determine the activities performed.

Crucible treats an Infrastructure Baseline as a reusable, versioned input rather than as a manually recreated or deployment-specific configuration.

The same approved Infrastructure Baseline revision can support more than one deployment when the applicable Deployment Targets, provider parameters, and acceptance criteria permit its reuse.

The composition result identifies the complete set of selected inputs made available for the lifecycle activity.

The result records:

• The composition identifier
• Each selected Baseline identifier
• Each selected Baseline revision
• Each source location
• The included application source revision, when applicable
• The applicable Crucible Description
• The applicable Platform Specific Parameters
• The selected lifecycle activity
• The composition result
• The associated Provenance
• The associated Traceability
• The generated Evidence

The composition result provides controlled inputs for subsequent image construction, dependency capture, compliance assessment, deployment, validation, and lifecycle-record preservation activities.

The linked leaf requirement pages remain the canonical sources.