[jorangreef]

The what here is the “system of record”. There might also be no other systems to write to/read from—and that's fine. The important thing is the order. Hopefully "Write Last, Read First" is unforgettable in that respect!

Or, can you suggest something pithier?

[layer8]

The article mixes two things: (1) That you should (depending on requirements) have one system of records while the other systems are merely systems of reference, and (2) that in that architecture, when (*) you write to both systems or read from both systems for the same logical record, then in the writing case you have to write to the system of records last, and in the reading case you have to read from the system of records first. The article however doesn’t make it clear that the titular rule is specifically (2), and that it is conditioned on (1) and on (*).

I have no suggestion for a better name off the top of my head. The issue I see is that you already have to know well its context and when it applies, also in order to not misremember it as “Write First, Read Last”, and to not mistake it as LIFO, or to relate it to a read-modify-write scenario in which you naturally would read first and write last anyway, though in a different sense. You see how the name is confusing?

[jorangreef]

I’m not convinced that it’s confusing, or that there’s a better alternative—but I appreciate your critique.

Do you not think if someone can remember those four words, they’re less likely to get it wrong?

If you could contribute some better suggestions we could consider them!

[layer8]

> Do you not think if someone can remember those four words, they’re less likely to get it wrong?

Only if they remember the words in the right order, which isn’t a given. There is nothing in the phrase that helps remembering the order, unless you already know how it has to work. What it probably does at least is remind you that the order matters.

Maybe find something that emphasizes that the master data (the data in the system of record) has the shortest storage duration (since its writes happen last and its reads happen first). Something like “keep central data central in time” (and peripheral data peripheral in time).

As a side note, while I know that “system of record” and “system of reference” are existing terms, they are a bit unfortunate in that they sound very similar, both abbreviating to SOR, and “reference data” having semantic overlap with “master data”, so “system of reference” could be taken to mean the system to be used as the reference, i.e. master data.