Getting started
Introduction
What Cairn is, in one page.
A cairn is a pile of stones that marks a summit or a path. Somebody puts down the first one, other people add theirs, and the pile becomes a landmark. Cairn the protocol is the same object in contract form: a pot with a goal, contributions that accumulate, and a rule for what happens when the goal is met or missed.
The idea
Cairn is a set of goal pots on Robinhood Chain. You open a pot, give it a target amount and a deadline, and either fill it on your own or let other people contribute. When the balance reaches the target, the pot is released to its beneficiary. When the deadline passes without the target being met, every contributor pulls back exactly what they put in.
There is one contract, deployed once, with no proxy and no upgrade path. Pot balances live in it and nowhere else.
What makes it different
A normal money pot is denominated in money. A Cairn pot is denominated in whatever ERC-20 the creator picks at creation time. That can be USDG, the Global Dollar on this chain, or any of the 47 tokenized equities that live here: TSLA, NVDA, SPY and the rest.
So "we each put in 40 USDG a month and by Christmas we have X NVDA" stops being a spreadsheet and becomes an on-chain object. The target is a number of NVDA. The contributions are NVDA. What comes out is NVDA.
Cairn does not swap anything. It holds the token you send it and gives back the same token. If you want a pot counted in NVDA, you contribute NVDA. There is no DEX call anywhere in the contract.
The shape of a pot
| Field | Meaning |
|---|---|
| name | A label, 1 to 64 bytes, stored on chain. |
| asset | The ERC-20 the pot is counted in. Decimals are read from the token, never assumed. |
| target | The goal, in raw units of that asset. |
| deadline | Unix seconds. Contributions stop after it. |
| beneficiary | Who receives the pot on release. Defaults to the creator. |
| shared | True: anyone can contribute. False: only the creator, and it always pays back to them. |
What it costs
0.50% of the pot, taken once, at release, out of the released amount and sent to the treasury. Nothing is taken on contribution and nothing is taken on refund. The fee is capped at 1.00% by a constant in the bytecode that nobody can raise. Once $CAIRN is live, a beneficiary holding enough of it pays no fee at all.
On top of that you pay chain gas, which on Robinhood Chain is a fraction of a cent per transaction.