Accounting is the core, not an add-on
Most systems bolt the books on at the end. Here the ledger comes first, and buying, selling, stock and production are simply the places where entries originate.
Chart of accounts
Structured per company and cost centre, with multi-currency where you trade in more than one.
Journals and taxes
Recurring entries, VAT and withholding handled at the point the document is raised.
Period closing
Lock a period once it is reconciled, with an audit trail behind every adjustment.