How Yumi works.

Overview

Yumi is a launchpad for pump.fun coins with one rule: a coin's first block belongs to the coin. A single wallet, the deployer, creates every coin and does it privately, so there is nothing for a sniper or a bundling dev to latch onto. The deployer also puts 2% of the supply on the line as a tripwire, and a coin whose ticker, name or picture repeats one already on Yumi never gets as far as a signature.

You bring the coin and 0.03 SOL. The coin itself is plain pump.fun: same curve, same graduation, same pool.

Launch a coin

1. Wallet. Phantom, Solflare, Backpack, or a wallet made on the spot in your browser. Connecting signs nothing.
2. The coin. Picture, name, ticker; a description and links if you like. The clone check runs while you type. With no website of your own, the coin links to its page on Yumi.
3. Optional bag. A dev buy in SOL, made from your wallet once the tripwire is done.
4. One signature. Your wallet is shown a single transfer of the launch fee to the deployer, labelled with your launch. The page refuses to pass on anything else. While you sign, your ticker and name are reserved for three minutes.
5. Follow it. Paid, in line, bundle out, live, tripwire. Usually a matter of seconds.
6. Done. The coin page and the address appear. If you asked for a dev buy, sign it now.

Your coin's address exists from the moment you prepare the launch, but it is computed on Yumi's server and revealed only after the coin is on chain. Until then not even you can point a bot at it.

The clone check

Only coins launched on Yumi are compared. Three things are checked:

• Ticker. Normalised before comparing: letters upper-cased, spaces and symbols dropped, accents removed, Cyrillic and Greek look-alikes swapped for Latin letters, digits read as the letters they imitate. $P3PE, $pepe, $PЕPE (Cyrillic Е) and $P E P E all normalise to PEPE, and PEPE can exist once.
• Name. An exact repeat is refused, and so is a near repeat that differs by a single letter (for names of four letters or more).
• Picture. Shrunk to a 9×8 grey thumbnail and reduced to a 64-bit fingerprint. Resizing, recolouring or recompressing a picture barely moves the fingerprint, so copies are caught.
• Reservations. Three minutes per launch while you pay, at most three unpaid launches per wallet.

On pump.fun itself anyone can launch anything. What they can't fake is the creator: every Yumi coin is created by the deployer.

Block zero

A launch is a single transaction carrying three things: pump.fun's create instruction, the tripwire's buy and a Jito tip. The deployer and the coin's mint key sign it, and it goes only to Jito's block engines, as a bundle. Either all of it executes, in that order, or none of it does, and no copy of it travels the public route where bots listen.

Each coin page then shows what the chain recorded: the slot the coin landed in, how many outside buys landed in that same slot, and what followed in the next ones.

The tripwire

Block zero is out of reach, so bots go for the very next one. The tripwire is waiting there: 2% of the supply, bought by the deployer at the curve's opening price inside the launch transaction. From the moment the coin lands, Yumi reads the curve four times a second. The first outside buy triggers a sale of the whole 2% into it; if nobody comes within about 2.5 seconds, it is sold back to the curve anyway.

• It's Yumi's money. The deployer funds it. Profit made off snipers stays with Yumi; the loss on a quiet launch (pump's fees on the round trip) is Yumi's too.
• It doesn't linger. About 2.5 seconds, sniper or not.
• It can sit out. If the deployer is short of SOL for it, the launch goes ahead without one, and the coin page says so.

Your dev buy

Optional, from your own wallet, in SOL. It is built only after the tripwire has finished, so it can never land in block zero and the tripwire never sells to you.

• 10% ceiling. While the coin is on its curve, Yumi won't build a buy that puts the dev above 10% of the supply. The form estimates the largest buy that fits.
• After that you're a holder like anyone. Trade here or anywhere. The ceiling applies to what Yumi builds; the bag check shows the real number.
• Selling half your bag inside the first hour, before the coin graduates, flags the coin as dumped and sets your grade to Flagged.

Fees

pump.fun routes each coin's creator fee to whoever created it. On Yumi that is always the deployer, which collects the fees of every coin in one claim every five minutes. Those fees pay for the tripwires and keep the launch fee at 0.03 SOL. Trades on Yumi carry no extra fee.

Refunds

• Paid nothing yet? Then nothing happened: the reservation lapses after three minutes, or at once when you press Back.
• Paid, and it didn't land? The launch is retried, one bundle at a time, with a bigger tip on each try and the same coin address every time. After four tries or ten minutes without success, the fee is sent back to the paying wallet automatically and your ticker and name are released.
• No double outcome. All attempts share one coin address, which can be created only once, and a refund is sent only after the chain confirms that address does not exist.
• Closed the tab while paying? Yumi finds the payment in the deployer's history and carries on without you.

Your wallet

Phantom, Solflare and Backpack work as usual. A launch asks your wallet to sign exactly one thing, the fee transfer; trades are the buys and sells you choose; flagging a coin is a signed message that moves nothing.

No wallet? Yumi can make one in your browser. The key is generated on your device, encrypted with your passcode (PBKDF2-SHA256, 310,000 rounds, then AES-GCM) and stored only there. It locks after 15 idle minutes. Export the key from the wallet panel and keep it somewhere safe: without the passcode or a backup it is gone.

Dev grades

A grade is attached to the wallet that launches. It starts at White and gets darker as that wallet's coins graduate cleanly.

Flagged replaces the grade while any of the wallet's five most recent coins carries a flag: the dev dumped in the first hour, linked wallets bundled the launch, or holders flagged it. Flags never come off a coin; the grade recovers once the flagged coin drops out of the last five. New wallets start at White, which means no credit yet, not a clean record.

Bag check and holder flags

For every Yumi coin the chain is read directly: the dev's balance next to the 10% ceiling, the ten largest holders, the wallets that bought in the first four blocks, and groups of holders whose first SOL came from the same wallet. A funder with thousands of transactions (an exchange, a bridge, a bot farm) is ignored, since it funds everybody.

Holders can flag a coin: one flag per wallet, signed by that wallet, for one of four reasons (dumped on holders, fake story or socials, copy of another coin, insiders hold most of it). A flag weighs as much as the tokens behind it, and only after those tokens have been held for 15 minutes. Five flags carrying 5% of the supply between them mark the coin as flagged by holders. You can't flag a coin you don't hold.

The deployer

Creator of every Yumi coin: …

It collects launch fees and creator fees, pays for every create, and funds each tripwire for its few seconds. The key that controls it is held by Yumi's server.

Limits, honestly

• The server holds the deployer's key, because launches are signed the moment they are paid.
• Block zero is measured, not guaranteed: a very fast bot can still land in the same slot. Block one is open to anyone; the tripwire is there to make it expensive.
• The clone check knows only Yumi coins. A copy launched straight on pump.fun is possible; it just won't have the deployer as its creator.
• pump.fun controls its own fees, and its takeover admin can reassign any coin's creator fees. Yumi can't prevent that.
• The 10% ceiling covers buys Yumi builds. Your key is yours, so the bag check reports what you actually hold.
• Linking looks one hop back. Several hops can hide a bundle; no link found is not the same as no link.

The numbers

FAQ

Is a Yumi coin a normal pump.fun coin? Yes: same curve, same graduation, same pool, visible on pump.fun, DexScreener and every terminal like any other.

Why is the deployer the creator instead of me? It is how originals stay provable and how the tripwire gets paid for. You are recorded as the dev, and your grade travels with your wallet.

Can I launch without a dev buy? Yes. Plenty of coins go out with no dev bag at all.

A sniper got in anyway? Then they paid the price the tripwire set when it sold them its 2%. The coin page shows exactly what landed in its first slots.