Meridian Field Services: instructional example, not project evidence
Impact analysis starts from a list, not diagram archaeology. One value-chain context (field service delivery) above four task-level flows; ceiling twenty-five elements per diagram, then collapsed subprocesses.
Lens law: operations structure here; the same assignment scenario lives experientially at Dana, current and future[1] and its system choreography at sequence views[2].
| Id | Flow (verb-noun) | Owner | Trigger | Systems & screens | Pair |
|---|---|---|---|---|---|
| FLW-01 | Assign job to technician (to-be) | M. Chen | Job reaches ready | Board, dispatch API, notification gateway (SCR-001[3], assignments[4]) | FLW-02 |
| FLW-02 | Assign job to technician (as-is) | M. Chen | Same | Phone, radio, whiteboard | FLW-01 · delta: two handoffs disappear (radio relay, whiteboard transcription); the accept decision moves from memory to the suggestion panel (delta[1]) |
| FLW-03 | Ingest job master (as-is, transitional) | E. Sandoval | 02:00 nightly | Legacy dispatch, adapter (INT-3[2]) | Retires at cutover: its to-be is no flow at all, stated |
| FLW-04 | Review override exceptions (to-be) | M. Chen (ops manager executes) | Weekly | Board exception view (US-3[5]) | n/a |
Reduced palette only: tasks, exclusive gateways, events, lanes, message flows, boundary events. The notification gateway is a second pool reached by message flow; the degradation path is a boundary timer, not a happy-path branch.
FLW-01: Assign job to technician (to-be). Fallback text: job reaches ready; the dispatcher reviews details; the board generates ranked suggestions (a two-second boundary timer degrades to the full technician list); the dispatcher accepts or overrides with a reason; the board records the assignment and notifies through the gateway pool (message flows); the technician confirms (a ten-minute boundary timer re-notifies and flags the dispatcher). Task citations live in documentation: SCR-001, POST /assignments, POST /overrides (endpoints[4]).
FLW-02 (as-is): the same outcome through phone intake, radio relay, and whiteboard update; eleven elements, three handoffs; the pair's delta is named in the inventory. Metrics where they decide: as-is handoff count three versus to-be one (handoffs concentrate defects; the observed radio-relay error motivated the redesign, observations[1]); cycle time instrumented at the dispatcher-to-technician lane crossing.
The unhappy path carries more review value than the happy path. Every task points at its exception or justifies its absence; absence is a claim.
FLW-03: Ingest job master (as-is, transitional; retires at cutover). Fallback text: a nightly two-o'clock timer fetches the legacy drop (message flow from the legacy pool); the adapter verifies the file checksum (a boundary error routes to quarantine-and-rerun and pages the on-call engineer); loaded records reconcile counts (a mismatch takes the same quarantine path); the run ends loaded or halted for rerun. The ISS-2 lesson, institutionalized (RSK-08[6]).
| Task | Exception path or justified absence |
|---|---|
| Generate ranked suggestions | Boundary timer, 2 s: degrade to the full list (quality scenarios[2]); no page, the dispatcher proceeds |
| Confirm assignment | Boundary timer, 10 min: re-notify once, then flag on the board exception view (US-3[5]) |
| Verify file checksum | Boundary error: quarantine, rerun, page on-call (DV-3[7]) |
| Review job details | Absence justified: read-only step; failure is a retry |
| Record assignment | Covered by the stale_version conflict contract (error registry[4]) |
Escalations cite the runbook (rollback and paging[7]); never restate it.
| Question | Owner | Answer by | Blocks |
|---|---|---|---|
| Does the confirmation-timeout re-notify happen once or twice before flagging (field-supervisor preference pending)? | M. Chen | Sep 19, 2026 | The FLW-01 timer parameters only |