Tagged append-only
3 pieces
- · 10 min read
Settlement And Reporting Are Projections Of One Record, Not Two Systems That Agree
When settlement and reporting each maintain their own copy of what happened, they will eventually disagree and nobody can say which one is right. Derived as projections of a single append-only record of trade transitions, disagreement stops being a bug you chase and becomes structurally impossible. The design question then moves to how a projection is rebuilt without inventing a second history.
- · 10 min read
Moving An Allocation Is A Transition, Not An Edit To Two Quantities
Shifting an allocation from one commitment to another moves real exposure, so it has to be recorded as its own transition with its own entry. Implemented as an edit to two numbers it leaves nothing to reconstruct, which means the move cannot be explained when it is challenged and cannot be made safe when two people do it at once. The operation is the record, not the resulting quantities.
- · 10 min read
A Correction Is An Entry, Never An Edit
An administrative correction applied by editing a figure destroys the ability to reconstruct how that figure reached its value, and it hides the fact that a correction happened at all. Recorded as its own entry, with a reason and an author, the balance still derives from the entries and the correction stays visible to everyone who later asks why the number moved. The hard part is the reason, not the arithmetic.