Alternate Info

Records that survive contact with reality.

If a requirement can be specified it can be sized, and sizing happens first. Names and addresses are folded consistently so comparisons mean something. The file ships with its own limitations written down.

Field provenance

Keeping the origin and date of each value with the record instead of flattening it away on delivery.

Overlap reporting

Where segments share records, stated rather than double-counted into a bigger total.

Rejection reasons

Every discarded row carries the rule that discarded it, in plain words.

Put the deadline on the table early; it changes what is sensible.