How swap Works, and the Three Decisions Behind It

The description fits in a sentence. You put a picture into a pool, one comes back from a stranger, and you find out what it is when you open it.

Underneath that sentence are three rules that are not the obvious way to build it. Each one costs something real, and each is there because the obvious version corrodes the thing it's supposed to support. This post is the reasoning, written down so it can be argued with.

If you just want to use the feature, it's here and you don't need any of this.

The loop, first

Four steps:

You send a picture or a gif into the pool. It costs sparks, and it sits pending until a person has looked at it.
Sending earns you a draw immediately.
The draw comes back blurred. You open it. A gif comes back for a gif, a picture for a picture, and you're never handed the same item twice.
If you like what you got, the stranger who sent it gets paid.

That's the whole thing. Everything below is about the parts that are load-bearing in non-obvious ways.

One: every reveal is identical

An earlier version of swap tagged each draw with a rarity tier, and the reveal animation scaled to match — the flourish ran anywhere from about a third of a second up to a second and a half depending on what you'd landed.

It was the most immediately satisfying part of the feature. It also had to go.

Here's the problem. The person who submitted the picture gets paid when the person who drew it likes it, which makes the like a payment mechanism rather than just a reaction. And the tier was telling you how impressed to be before you had looked at the picture. A long, elaborate reveal primes you to like what's behind it; a short one primes you not to. That is a system paying people based on a judgement it leaned on before the judgement was made.

So the tiers are gone. Every reveal is now the same half-second, every time, whatever is behind it. What's behind the blur is the only variable, and you're the only thing forming an opinion about it.

The fixed half-second is downstream of the same decision. When the reveal was a reward it could afford to be long. Now that it's punctuation, it has to be short enough that nobody ever wants to skip it — because it fires on every draw, forever.

Two: sending pays nothing

You are not paid for submitting. Not a token amount, not a first-time bonus. The only way a submission earns anything is if the person who draws it likes it.

The obvious design pays for supply, on the grounds that the pool needs supply. The reason we don't is that "supply" and "supply worth opening" are different quantities, and only the second one is the product.

Pay for the act of submitting and the act of submitting is what gets optimised — which in practice means whatever is cheapest to produce, submitted as often as the limits allow. Pay only for being liked, and the sole route to earning is sending something a stranger is glad they opened. Same feature, opposite pressure.

This reads as stingy right up until you picture the alternative pool. A pool worth opening is the entire product; nothing that degrades it is worth the volume it buys.

There's a corollary worth keeping: because sending carries no earning pressure, there's no reason to send anything except that you want to see what comes back. That's a better motive than a payout, and it's free.

Three: nothing enters the pool unscreened

Every submission sits pending until a person has looked at it. Not a filter, not a queue that drains automatically under load — a person.

The cost is real and we're not going to dress it up: this is the slowest part of the loop, your submission does not appear instantly, and that is not going to get faster. It is a deliberate trade against the alternative, which is unreviewed images from strangers being served at random to people who opted into a surprise. There's no version of that we'd want to run.

If something does get past it, the report goes to a person — the same route as any other report on the site.

What it costs, and where sparks come from

A swap costs sparks. Sparks arrive three ways, listed in the order a new account can actually reach them:

every level from the second onward pays out enough for a swap — the one that works on day one
someone liking what you sent — requires having swapped at least once
a short ad, from level 2 — not before level 2, which is a real restriction rather than a formality

Levels come from talking to people, so the practical path into swap runs through the chat rather than around it. That's intentional: a picture pool attached to a chat site should be fed by people who use the chat site.

Two smaller things, since they come up

You need an account, not just a session. Guests can chat; swap needs an account, because what it spends lives on the account rather than on the browser tab. One screen, no email.

Swap media outlives your messages. Chat clears within a day, for reasons we've written about at length. A swap submission has to stay drawable and likeable for as long as it's in the pool, so it doesn't follow the same clock. If you're deciding what to send, that's the relevant difference and it's worth knowing before you send rather than after — the same judgement call as sharing a photo anywhere else in chat, with a longer tail.

Try it

Put something in the pool and see what comes back. And if it hands you something dull — that's the honest version working. Every draw looks identical on the way out.