Part 4 defines the Phase 0 implementation Baseline. It identifies selected implementation technologies, implementation artefacts, mappings, DDS Topics, IDL structures, generated types, QoS profiles, scripts, Repository organisation, Developer Handbook requirements, governance rules, and Traceability relationships.

Part 5 defines the Phase 0 Deployment, testability, operation, Observation, and Evidence approach. It identifies how the implementation artefacts defined in Part 4 are deployed, started, exercised, observed, reviewed, and evidenced.

Part 4 does not define Deployment topology, runtime environment configuration, operational runbooks, test execution results, Evidence packages, dashboards, Kubernetes or K3s Deployment, Crucible scenarios, or acceptance Evidence. Part 5 owns those concerns.

Part 5 does not redefine the implementation artefacts defined in Part 4. It deploys, tests, observes, operates, and evidences those artefacts.