DOCS
How SPROUT works
Every launchpad lets you launch a coin against the money. SPROUT lets you launch it against somebody else's coin as well: ETH, one of the coins Robinhood Chain already trades, or a coin launched here. The coin you pick is the other side of your pool, for good, and it is what your chart measures.
01 The denominator is a choice
A pair has two sides. Everywhere else the second side is ETH, which means every chart you read is really your coin divided by the market. Here you pick it. MOTH/ROBIN is not a price in dollars, it is a claim: one MOTH is worth this much ROBIN. When the number goes up, MOTH beat a specific coin whose holders are watching, and every buyer of MOTH had to hold ROBIN first.
DexScreener and the terminals list the coin exactly that way, as a pair with its parent, because the pool is an ordinary Uniswap v4 pool on Uniswap's own PoolManager.
02 One root, five generations
The tree starts at ETH. The well-known Robinhood Chain coins hang off it as outside parents: they were not launched here, but anyone can launch under them. Coins launched under a coin launched here go one generation deeper, to a hard cap of generation 5.
| Parameter | Value | Notes |
|---|---|---|
| Total supply | 1,000,000,000 | Minted once, no mint function, no owner, no transfer tax |
| Team allocation | None | The whole supply goes into the pool |
| Parent | ETH, any token, or a coin launched here | Fixed at launch |
| Opening market cap | About $4,000 | In the parent's units, at the parent's price when you launch |
| Market | One Uniswap v4 pool | COIN/PARENT, 3% fee, one hook that lets only the launcher add liquidity |
| Liquidity | Locked for good | Held by the launcher, which cannot remove it |
03 Launching needs no seed
The launcher mints the billion coins and puts all of them into the pool as one single-sided position: a range that starts at the opening price and runs to the top of the book. At that price the position holds only your coin, so nothing else has to be paid in. The coin opens with a market cap and a full book, and a launch costs gas.
If you want to hold your coin, the first buy runs in the same transaction, the moment the pool opens, so nobody gets in before you. Paying in a token rather than ETH, it needs one approval first.
The uncomfortable half: an opening market cap is not money in the pool. A new coin at $4,000 has coins on one side and nothing on the other. Every sale is paid out of what the buyers before it put in.
04 The fee
Every swap in every pool pays 3%, charged by the Uniswap v4 pool itself in the token paid in: the parent on a buy, the coin on a sell. It accrues to the locked position, and only the protocol owner can collect it. Collecting takes the fees and never the liquidity. Trades from DexScreener, the terminals and aggregators pay the same 3%, because they trade the same pool.
A round trip costs about 6% before price impact. That is deliberate and it is high; weigh it before you trade.
05 Succession
The pad ranks every heir against its parent by market cap, live. A ratio above one means the child is now worth more than the coin it launched under, and the Succession page lists them. It is a standing, not a switch: nothing on chain moves when a child overtakes its parent.
06 The lock
The launcher contract owns every position and has no function that removes liquidity. There is no owner switch that can pause, upgrade, mint or withdraw. The only things the owner can do are collect fees and hand ownership to another address.
Every pool carries one hook, and it does one thing: before any liquidity is added, Uniswap asks it, and it refuses everyone but the launcher. Without it anybody could park liquidity in the price band where trading happens and take a share of the fee. It never touches a swap.
07 Reading a pair
A price on SPROUT is quoted in parent units, read from the pool's own price. Everything in dollars is derived and never stored:
usd_price = product(price at every hop down to ETH) × eth_usd
market_cap = usd_price × 1,000,000,000
24h change = measured against the parent, not the dollar
An outside parent's own price comes from the market board, which reads it from its most liquid pools. So a coin can print +14% against ROBIN and still be red in dollars, because ROBIN fell harder.
08 Outside parents
Any token with code on the chain can be a parent: the launcher does not need to buy it, because launching needs no seed. The pad shows the best performing Robinhood Chain coins to pick from, and accepts any address. A token that takes a fee on transfer cannot be traded against, since the launcher checks that exactly what was paid arrived; launching under one is pointless and buying is refused.
09 What each action costs in gas
Measured against Uniswap's own PoolManager on a fork of Robinhood Chain mainnet.
| Action | Gas used | At 0.05 gwei |
|---|---|---|
| Launch, paired with ETH, with a first buy | ~672,000 | ~0.00003 ETH |
| Launch, paired with a token, with a first buy | ~698,000 | ~0.00003 ETH |
| Buy | ~114,000 | ~0.000006 ETH |
| Sell | ~125,000 | ~0.000006 ETH |
10 Risks, and who this is for
This is the long version of the notice you agreed to on the way in. It is not boilerplate we hid at the bottom: everything below is a way you can lose money on this pad, written out.
Trading risk
Tokens launched here can be highly volatile and highly illiquid. A pool with a thin reserve moves on a small trade, and the coin you bought may have no bid at all when you want out. You may lose every unit of value you put in. Nothing in the mechanics of this pad, not the parent pairing, not the locked liquidity, not the fee, protects a price. A coin opens at a market cap with nothing on the other side of the book: every sale is paid out of what earlier buyers put in.
No financial advice
SPROUT provides information and tools, not investment advice. The rankings on Succession and the ordering on Explore are arithmetic on public reserves, not endorsements, and a coin appearing on this site is not a claim that it is worth owning. No return is promised, implied or guaranteed by anyone involved in this build.
Your responsibility
Research a coin before you touch it, protect your wallet, and read every approval before you sign it. Smart contracts can fail, and this one is young: it is tested and the tests are public, but tested is not the same as unbreakable. Scams can be launched here exactly as they can anywhere with a permissionless factory. On-chain transactions are irreversible, and gas plus trading fees apply to everything you do. Prices, charts and holder counts on this site can be delayed or incomplete, so confirm the details in your wallet rather than on our page.
Who can use SPROUT
SPROUT is not available to U.S. citizens. By continuing past the entry notice you confirm that you are not a U.S. citizen, that you understand these risks, and that you are legally permitted to use SPROUT where you live. That confirmation is a self-declaration: we do not verify identity or citizenship, which puts the obligation on you rather than on a check we pretend to run.
The CFTC publishes plain-language guidance on digital-token risk, written by people with no stake in whether you use this pad. It is worth ten minutes.
11 What this build actually is
Two contracts written for this pad and published with it: HeirloomToken, a plain fixed-supply ERC-20 every coin is a clone of, and HeirloomLauncher, which mints each coin, opens its pool on Uniswap's own v4 PoolManager, locks the supply in it, routes buys and sells, quotes them with the pool's own swap maths, and lets the owner collect the fee; and HeirloomHook, the pools' one hook, which lets nobody but the launcher add liquidity.
They are covered by a test suite that runs against the canonical Uniswap v4 PoolManager: opening at the chosen market cap with the whole supply single-sided in both address orders, fills equal to quotes in ETH and in a token, the first buy and its minimum, the 3% reaching only the owner and never the liquidity, an outsider refused when adding liquidity, the coin's address following the launcher's random salt, a book bought out and the rest refunded, fee-on-transfer parents refused, and bad input refused. The same bytecode was deployed onto a fork of Robinhood Chain mainnet and launched under ETH and under ROBIN, traded and collected there, and the site was driven end to end in a browser against that fork. The front end reads every coin, price, pool and holder from the chain and invents none of it.
What that does not make it: audited. No third party has reviewed these contracts. Start small.