The GitLab project lives at simpl-open/data/supporting-data-services/distributed-execution/distributed-execution, so CI_REGISTRY_IMAGE ends in the project name twice. The pipeline pushes to CI_REGISTRY_IMAGE and nowhere else, so the earlier one-segment path named an image nobody builds - the same mismatch that field-level-pseudo-anonymisation and dataframe-level-anonymisation carry today.
Changelog: fixed
yaml/sandbox/values-sandbox-gitea.yaml carries the registry coordinates, the pull secret both namespaces need, and the commit SHA the two images share. The sandbox registry rejects anonymous pulls, so a payload namespace without its own pull secret leaves the dispatching op waiting on a pod that never starts - readiness check L4 now says so.
Changelog: added
Canonical location for documentation, example workflows and reference service implementations covering distributed execution patterns. Covers AC1-AC4: execution-target selection, decision support, readiness checks and code-level linkage. Tightly coupled jobs and the loosely coupled subprocess transport are verified by the test suite; the Kubernetes pipes transport is implemented but not yet cluster-run and is marked as such in the guide.
Changelog: added