Andrew Fribush

fig. 2.19.2: two devices answer one card before either syncs: the op-queue keeps all five answers in either order

fig. 2.19.2 · two devices answer one card before either syncs: the op-queue keeps all five answers in either order.
W2 WRITES LAST: THE OP-QUEUE FOLDS ALL FIVE ANSWERS; LAST-WRITE-WINS KEEPS W2’STHREE AND OVERWRITES W1’S TWOW2 WRITES LASTW1 WRITES LASTONE MARK IS ONE ANSWER: DOT CORRECT, RING WRONG, STRUCK OVERWRITTEN.TWO DEVICES ANSWER THE SAME SPANISH CARD, POR OR PARA, BEFORE EITHER SYNCSW1 ANSWERSCORRECT, THEN WRONGW2 ANSWERSCORRECT, THREE TIMESOP-QUEUE, AS SHIPPED: FOLDS EVERY ANSWER AS A +1 COUNTSERVER ROWW1W2ATTEMPTS5SUCCESSES4MISSES1STRENGTH3STREAK3NOTHING LOST: ATTEMPTS, SUCCESSES AND MISSES AGREE IN EITHER ORDER; STREAKFOLLOWS ARRIVALLAST-WRITE-WINS PLUS A TOMBSTONE: THE LAST WRITER REPLACES THE ROWSERVER ROWW1W2ATTEMPTS3SUCCESSES3MISSES0STRENGTH3STREAK3W2 LAST: W1’S 2 ANSWERS OVERWRITTEN

source: vocabinator sync design note lines 137-148 (the worked two-device example); research/2026-08-19-persistence-upgrade.md lines 162-175 · syncMerge.data.ts

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Andrew Fribush, software and computer engineer in Austin. I build consequential systems where software meets institutions: finance, healthcare, commerce, government data, and the mechanisms that govern AI agents. Taking new engagements: hello@andrewfribush.com.