engineering

The Log

Everything, in order.

The complete stream: essays, shipped changes, and notes, newest first.

Note

The backup test

A copy of the system will travel. Restorations, support, the ordinary movement of data that every durable product eventually does. The test is simple. After the copy exists, can it be used to impersonate someone? If yes, something that can authenticate was stored as if it were merely a record.

The cheaper decision is to store only what can verify. A value that confirms a claim, without being spendable as that claim, survives a copy. A value that can be replayed as-is does not. We apply that test anywhere a secret or a proof of identity would otherwise sit next to ordinary data.

The rule is not a particular mechanism. It is a placement: anything that can be spent as access does not belong in the record.

Note

The chart is not a slide

A structure that lives in a deck is already out of date. Someone drew it for a meeting, the room nodded, and then the organisation kept moving. By the next quarter the slide is a souvenir: still presented, no longer true.

The interesting problem is not drawing boxes. It is refusing a second picture of the organisation, one that can drift from the one people actually work in. Prism treats the chart as the record, not as an illustration of a record kept somewhere else. If the picture and the reporting line disagree, the picture is wrong.

That is a placement decision. Illustration is cheap and it ages in a drawer. A single picture, the one the work runs on, is the only one that can stay honest.