One value. Three sources. A trail you can follow.

Items master. Every cell points back to the system that produced it.

The item master is the shared picture made visible. The view below shows one parent item with its indented BOM three levels deep. Every line is kept in sync with the systems of record at the field level. Each row carries a stamp on the cost cell showing where that number came from. When SAP and a supplier email disagree, the conflict surfaces in the cell instead of quietly being overwritten.

Six things, six kinds of source, a rule for how stale each can get.

The grid below shows Polymr's six core things against the six kinds of source that feed them. Each cell shows how old the last reading is. If a cell is older than the allowed limit, Polymr refuses to read from it instead of quietly using stale data.

Every cell remembers who supplied it.

The trail behind a value is not stored in a separate audit table off to the side. It lives in the same place as the value. Each field carries a value, the system that produced it, the document the value came from, the person who confirmed it (if anyone), when it was observed, and how confident we are. Old values are kept, not overwritten, so you can pull the history of a single field in one query.

When Polymr reads a value, it reads the trail too. A recommendation that cites a cost basis cites a PO line. The PO line cites a supplier email. The email is one click away in the console. Every write Polymr performs can be rebuilt from the documents that produced it.

Polymr refuses to act on stale data.

For every kind of source, we set a limit on how old the data is allowed to be. Inventory streams in real time, because a planning workflow that reads stale inventory proposes the wrong things. Supplier data pulled from a portal that updates twice a week carries a limit measured in hours. Each limit is part of the contract for that source, and Polymr enforces it as a hard rule, not a soft warning.

When Polymr reads a value that is older than its limit, it gets back a "stale" answer instead of the value. The workflow that needed the field stops and writes an audit row. Nothing quietly runs against an old number. The fix is to check the connector that fell behind, and the audit trail tells you exactly which source and which field failed in one query.