We keep checking, so you can forget about it

Before any of this, a price was read once on the day somebody pasted the link and never looked at again — so a board was a wall of figures that were true months ago. For something people fill in October and shop from in December, that is the wrong default.

Now every price carries the day we last checked it, and the checking happens on its own. When a price falls, the card shows what it was as well as what it is: the old figure struck through, in the same serif, smaller and faint. Not green, not a badge, not a starburst — a saving is the one thing everybody wants to shout about, and shouting about it is how a board starts looking like a shop.

Far less than you would think, and that is the feature. An alert you can’t trust is worse than no alert, because after two bad ones nobody opens the third. So a drop has to clear a percentage and an amount before it earns a word — a 40p wobble on a £300 camera is noise, and so is 30% off something that costs £4.

Things Rivori sees and deliberately says nothing about:

• A shop’s own crossed-out price. Shops leave those up long after the sale ended, or set them equal to the real price and forget. A saving we invented becomes a drop alert we invented.
• A price that fell through the floor. An 85% collapse is almost never a sale; it is a page that quietly started describing an accessory, a replacement lens cap where the camera used to be.
• A change of currency. $489 becoming €412 is a shop deciding where it thinks you are, not a discount.
• An out-of-stock offer. The cheap one is the last odd size nobody wanted, and it isn’t there to buy.
• A price going up. The card updates quietly. Nobody needs a message about that.
• A price you typed yourself. If you corrected a scrape, that number is yours and nothing overwrites it.

There is also a cap on how many of these can reach you in a day, for the same reason a sale weekend shouldn’t put fifty emails in one inbox.

New accounts have it on. Accounts that existed before this was built have it off, and switching it on for them would have been the wrong call — it would have sent alerts nobody asked for to every inbox that already had a full board, and that is the one kind of message you cannot un-send. If you signed up a while ago, it’s one switch in your notification settings.

Alerts land in your Rivori inbox and ride along with your notification email if you have that on. Price drops are their own category, so you can have them without having anything else, or have everything except them. One click unsubscribes from any of it, from inside any email.

Rivori reads prices from shops’ own pages and shops change them whenever they like. The figure on a wish is the last one we saw, dated so you know how old it is — the shop’s price is the real one. That is worth saying plainly rather than in a footnote, and it is the same reason every Buy button takes you to the shop rather than trying to be one.

What we’d like to add next is a number you choose rather than one we decide is significant — “tell me when this is under £40” — and a line showing what a thing has actually cost over time, so you can tell a real price from a fortnight of theatre. That’s on the roadmap.