Lesson 07 · 6 min

The Audit Trail, and the Book Today

WorkflowSteps chain events into a replayable history. Fold the line and you get today's position.

The auditor's question

Eighteen months in, Goldman's risk desk gets the question every desk eventually gets: why does this position say USD 6,000,000, who approved the October change, and when exactly did Pershing Square drop off the trade? In most shops the answer is a week of spreadsheet archaeology. Here it is a walk along the line you have been drawing all module, because every event travels inside one more wrapper: WorkflowStep, the envelope that records who said what, when, and in reply to which earlier step.

Key ideas

WorkflowStep is the envelope
It wraps the businessEvent with eventIdentifiers, at least one timestamp, the party and account context, and messageInformation: the difference between an event and a message about an event.
The chain is explicit
previousWorkflowStep points each step at the one before, so the history is a linked chain rather than a pile of records sorted by hope. lineage can also reference related trades and steps directly.
Corrections append, never overwrite
action is New, Correct, or Cancel. A bad booking is fixed by a new step that says Correct; the bad step stays on the chain, visibly wrong and visibly corrected.
Position is a fold
Nothing in the model stores "the current book" as authority. Today's position is derived by replaying the line, which means any party holding the same events computes the same book. Disagreement becomes a diff, not a dispute.

One step, on the wire

{} workflowStep wrapping the October unwind, trimmed

{  "businessEvent": "… the October partial termination …",  "eventIdentifier": [    {      "assignedIdentifier": [        {          "identifier": "PSLP-EVT-008214",          "version": 1        }      ],      "issuer": "QW46WU5Y2RDY41BTIO66"    }  ],  "timestamp": [    {      "dateTime": "2026-10-15T14:02:11Z",      "qualification": "eventCreationDateTime"twelve kinds of clock time, each named    },    {      "dateTime": "2026-10-15T14:02:43Z",      "qualification": "eventSentDateTime"    }  ],  "action": "New",corrections append; nothing is erased  "party": [    "… Pershing Square, Goldman Sachs …"  ],  "previousWorkflowStep": "… the July reset's step, by reference …",the thread back through history  "messageInformation": {    "messageId": "5821647",    "sentBy": "QW46WU5Y2RDY41BTIO66"  }}

timestamp is required and plural because "when did this happen" has many true answers: created, sent, submitted, confirmed. EventTimestamp forces each one to say which it is.

The book today

Now fold the line. Born at USD 10,000,000 at execution. Two resets recorded, the contract untouched. Down to 6,000,000 in the October unwind. Reset again. Novated to Bank of America. Replay those events and Goldman's book today reads: USD 6,000,000, facing Bank of America, with every number on that line traceable to an event, every event to a step, every step to timestamps and a sender. The answer to the auditor is not an explanation. It is the data, replayed.

Try itOpen WorkflowStep in the explorer and walk timestamp into EventTimestampQualificationEnum. Twelve named clocks, and now you know why a trade needs all of them.

◆ Checkpoint

01A booking error from last week is fixed by:

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