Implementing UUID v7 by hand: time-sortable keys and the same-millisecond trap

UUID v7 uses a millisecond timestamp in the leading bits to make primary keys sortable by generation order, improving B-tree index performance. The author implements it in the browser using crypto.getRandomValues, avoiding Math.random(). A trap occurs when multiple UUIDs are generated in the same millisecond, requiring additional randomness to maintain uniqueness.