A business management system, drawn honestly

The key facts

• The centre: one shared record — the single dataset every module reads and writes.
• The modules around it: inventory, purchasing, orders, customer portal, invoicing, reporting.
• The boundary box: accounting (Xero/MYOB) is a connected system of record, not a module — approved invoices cross; nothing else needs to.
• What stays outside the diagram: HR, payroll, MRP scheduling, storefronts — BSimple deliberately leaves them out.

The diagram, in text

Draw a wide box labelled the record. Inside it, side by side:

• Inventory — products, quantities per location, batches, costs. The truth about what you hold.
• Purchasing — reorder levels, purchase orders, goods receipts, price variance. How stock arrives.
• Orders — portal, phone and marketplace orders, picking and packing, status. How stock leaves.
• Invoicing — approval, the invoice, payment status mirrored from accounting. How leaving stock becomes money.
• Portal — each customer's own products, pricing and ordering path.
• Reporting — order, invoice and stock values in one view.

Arrows connect them because they share the dataset: a receipt changes what the portal can promise, an approval changes what accounting sees. Then, outside the big box, one smaller box: accounting (Xero or MYOB), joined by a single labelled arrow — approved invoices in, payment status back. That arrow is the boundary, and the honesty of any "business management" diagram is measured by whether it has one. What a business management system is covers the definitions; the process comparison shows how this differs from BPM tooling.

How BSimple fills the diagram

We build BSimple, so weigh that — and the honest description is that the diagram above is roughly our architecture. One record carries inventory, purchasing, orders, the customer portal, invoicing and reporting; recipes and batch production sit with inventory; the audit trail sits under all of it. The accounting boundary is real: approved invoices push to Xero or MYOB, payment status mirrors back, and the books remain the accountant's system of record. Around the edges, a public REST API and an MCP endpoint let your own tools and AI assistants read the record.

Just as honest is what is not in the diagram: no HR, no payroll, no MRP scheduling, no storefront — BSimple is deliberately the layer between spreadsheets and an ERP, from $180/month (AUD). The features overview walks each module, and the trial draws the diagram with your own products in it.