Rebuild the accounting-entry-then-journal architecture into D365's direct posting model — classifying every journal source, translating twelve posting patterns into posting profiles, and proving equivalence by replay rather than by configuration comparison.
The posting engine is where a PeopleSoft migration stops being a design discussion and becomes an accounting one. It is also the workstream most likely to be underestimated, because the source's architecture makes the problem look like a data-movement task when it is a structural one.
The first deliverable is not a mapping. It is a journal source map — the playbook lists it among required discovery outputs — and its purpose is to force one of four decisions for every flow that currently reaches the General Ledger through Journal Generator.
The source package identifies twelve posting patterns that any PeopleSoft programme must resolve. Nine are marked mapped, two partial, and one a gap. The status is a statement about how much design work remains, not about difficulty.
The voucher post pattern is the highest-volume accounting flow in most estates. In the source it debits expense, asset, inventory or project distribution ChartFields and credits the accounts payable liability, through Payables accounting entries that Journal Generator subsequently converts.
The Billing and AR invoice pattern debits the receivable control account and credits revenue, freight, tax and discount accounts. The target maps the receivable to the customer posting profile summary account, and the credit side to sales and tax posting configuration.
Receipt accrual debits inventory or expense and credits a receipt accrual account. The target expresses it through inventory posting, with the accrual account coming from item-group inventory posting configuration.
Asset acquisition debits asset cost and credits an asset clearing account or the payable. Depreciation debits depreciation expense and credits accumulated depreciation. Both map to asset posting configuration by asset group and Book.
The source balances transactions crossing unit boundaries using affiliate ChartFields and balancing rules, producing due-to and due-from entries. The target maps this to intercompany accounting configuration plus optional reporting dimensions, and the rule is marked partial with the plain note that this is often a redesign, not a direct…
The commitment-control pattern debits budget, pre-encumbrance or encumbrance ChartFields and credits offset, reserve or control accounts. The rule is marked gap — the only one in the set — with the note that only partial D365 parity exists.
The crosswalk is one row per posting event, and it is built from observed accounting, not from configuration.
Select a representative set of real source documents — vouchers of each retained type, invoices of each billing line type, receipts, issues, asset acquisitions, depreciation runs, project cost distributions, and every flow classified as a journal import.
The posting engine is the workstream where the source's defining architectural habit — accounting entries first, journals second — has to be deliberately unlearned.