Wind the coil
Pick your stocks and how much of each. Skein states the basket per unit and offers 1,000 units of it, so every fraction divides exactly — for every strand at once, whatever their decimals.
A skein is yarn wound into a coil — many strands you can carry as one. Wind up to 12 of your tokenized stocks into one lot, name one price in dollars, and publish it. A buyer takes the whole coil or any fraction of it — and a fraction is a fraction of every strand, in the same transaction. Nobody picks the Nvidia out of the middle and leaves you the rest.
Your shares stay in your wallet until somebody actually pays for them. There is no vault, no escrow contract and nothing of ours in between.
Pick your stocks and how much of each. Skein states the basket per unit and offers 1,000 units of it, so every fraction divides exactly — for every strand at once, whatever their decimals.
One approval per strand, for exactly what the lot offers — never unlimited — and one call to Seaport. Because you are the seller and the caller, Seaport needs no signature at all. The order lands in Seaport's own log, and that log is the board. There is no server.
A buyer takes any number of units, down to 1/1,000 of the coil. They pay you, and every stock leaves your wallet in the same transaction — or none of it does. Take the lot down whenever you like.
Selling a basket through pools is not one trade, it is one trade per stock — and each one slides down its own curve. We measured what that costs on this chain, at four sizes, in one block, against Robinhood's own prices. The answer is not flattering to us everywhere, so here is all of it.
What the pools charge for the showcase basket (AAPL, NVDA, TSLA, SPY at $25,000. Essentially free. 14 of the 44 stocks here cost under a quarter of a percent at that size. If your basket is only big names, use the pools — you will beat any lot you could write.
The same measurement on the 8 dearest names (RIVN, NBIS, ORCL, TTWO, SNDK, NFLX, USAR, AMD) at $25,000 — up from 0.95% at $1,000. And at $100,000 the pools simply refuse 11 of the 44 outright. A person can price what a curve will not.
Skein is not a better price. It is a different price — one you and a buyer agree, instead of one a curve imposes. On deep names the curve wins and the page says so on the lot itself: every coil on the board is priced against Robinhood's own feed and against what the pools would charge for the same shares, and when the pools are cheaper you see that before you sign. The median stock costs 0.36% more at $25,000 than at $1,000; the worst costs 81.16% more. Measured at block 67,496,374.
Cost of a sale against Robinhood's own price for the same shares, best single pool, at block 67,496,374. Negative means the pools paid more than the feed. “Refused” means no pool could fill it at all.
| Stock | $1,000 | $5,000 | $25,000 | $100,000 | Pools |
|---|---|---|---|---|---|
| GLDGLD SPDR Gold Trust | −0.57% | −0.56% | −0.52% | −0.41% | 6 |
| SPYSPY SPDR S&P 500 ETF Trust | −0.32% | −0.31% | −0.31% | −0.29% | 4 |
| QQQQQQ Invesco QQQ | −0.15% | −0.14% | −0.13% | −0.07% | 3 |
| GOOGLGOOGL Alphabet Class A | −0.14% | −0.13% | −0.11% | −0.01% | 5 |
| METAMETA Meta Platforms | −0.21% | −0.13% | 0.02% | 2.72% | 3 |
| LLYLLY Eli Lilly | −0.19% | −0.12% | 0.06% | 1.96% | 8 |
| SLVSLV iShares Silver Trust | −0.13% | −0.08% | 0.12% | 0.84% | 3 |
| AAPLAAPL Apple | 0.04% | 0.06% | 0.13% | 0.48% | 7 |
| NVDANVDA NVIDIA | 0.15% | 0.15% | 0.16% | 0.17% | 7 |
| AMZNAMZN Amazon | 0.12% | 0.13% | 0.18% | 0.37% | 3 |
| BABABABA Alibaba | −0.46% | −0.35% | 0.18% | 2.88% | 5 |
| SGOVSGOV iShares 0-3 Month Treasury Bond | 0.17% | 0.17% | 0.19% | 0.50% | 4 |
| TSLATSLA Tesla | −0.14% | 0.07% | 0.22% | 0.74% | 4 |
| SPCXSPCX Space Exploration Technologies Corp. Class A Common Stock | 0.22% | 0.22% | 0.24% | 0.32% | 6 |
| HIMSHIMS Hims & Hers Health | 0.35% | 0.36% | 0.40% | 0.56% | 5 |
| AMCAMC AMC Entertainment | 0.28% | 0.32% | 0.43% | 0.85% | 8 |
| CRCLCRCL Circle Internet Group | 0.24% | 0.27% | 0.44% | 1.04% | 5 |
| DJTDJT Trump Media & Technology Group | 0.11% | 0.16% | 0.45% | 1.65% | 3 |
| COSTCOST Costco | 0.11% | 0.15% | 0.50% | 1.39% | 4 |
| INTCINTC Intel | −0.25% | −0.02% | 0.56% | 2.99% | 2 |
| GMEGME GameStop | 0.33% | 0.36% | 0.57% | 2.25% | 6 |
| MSFTMSFT Microsoft | 0.46% | 0.48% | 0.61% | 1.09% | 3 |
| MUMU Micron Technology | 0.64% | 0.66% | 0.78% | 1.45% | 2 |
| MRNAMRNA Moderna | −0.27% | −0.06% | 1.02% | refused | 4 |
| RDDTRDDT | 0.51% | 0.73% | 1.12% | 1.51% | 4 |
| IBMIBM IBM | 0.17% | 0.46% | 1.14% | refused | 7 |
| USOUSO United States Oil Fund | 0.99% | 1.17% | 1.22% | 1.41% | 3 |
| COINCOIN Coinbase | 0.71% | 0.80% | 1.26% | 3.08% | 2 |
| PLTRPLTR Palantir Technologies | 0.55% | 0.67% | 1.35% | 2.20% | 3 |
| RBLXRBLX Roblox | 0.60% | 0.80% | 1.55% | 6.38% | 5 |
| TSMTSM Taiwan Semiconductor Manufacturing | 1.18% | 1.25% | 1.58% | 2.97% | 7 |
| DELLDELL Dell | 0.21% | 0.47% | 1.60% | 4.94% | 4 |
| LULULULU Lululemon | 0.33% | 0.52% | 1.77% | refused | 5 |
| AMDAMD AMD | 1.19% | 1.51% | 2.20% | 3.47% | 4 |
| USARUSAR USA Rare Earth | 0.32% | 0.63% | 2.21% | refused | 1 |
| NFLXNFLX Netflix | 0.35% | 0.49% | 2.22% | refused | 4 |
| SNDKSNDK Sandisk Corporation | 1.47% | 1.67% | 2.67% | 6.69% | 2 |
| TTWOTTWO Take-Two Interactive Software | 0.33% | 0.52% | 2.69% | refused | 5 |
| ORCLORCL Oracle | 2.10% | 2.43% | 4.02% | 10.11% | 1 |
| NBISNBIS Nebius Group | 1.90% | 3.08% | 8.99% | refused | 2 |
| RIVNRIVN Rivian Automotive | −0.09% | 0.21% | 81.07% | refused | 5 |
| ASMLASML ASML Holding NV | 1.33% | 2.51% | refused | refused | 4 |
| EWYEWY iShares MSCI South Korea fund | 1.79% | refused | refused | refused | 4 |
| RKLBRKLB Rocket Lab Corporation | 1.85% | 2.96% | refused | refused | 1 |
A lot is not a shop where a buyer picks the good bits. Seaport applies one fraction to every item in the order, and reverts unless it divides exactly. Take a tenth of a coil and you take a tenth of the Apple, a tenth of the Nvidia and a tenth of the thin one nobody wanted — or the transaction does not happen.
This is the whole reason Skein states a basket per unit and multiplies by 1,000. Stated as totals, a buyer asking for a third would revert on whichever stock's total was not divisible by three — and which one that is depends on its decimals, so it would fail for some baskets and not others, unpredictably.
If a seller sells one of the twelve stocks somewhere else, the coil cannot be delivered whole. The board reads every strand's balance and allowance at the same block and says exactly how much of the lot is still deliverable — and which strand is the limit — instead of letting a buyer find out from a revert.
A lot that has been taken down says so. Seaport clears its own “validated” flag on a cancel, so a cancelled lot also reads as “never seen”; saying that about a lot its seller has just taken down would be a lie, and the board checks cancelled first.
This chain carries counterfeits of every real name. Nothing here starts from a name: every token answered symbol, name and decimals at one pinned block, every pool is the one Uniswap's own factory returns, and every price is the feed a Morpho market lending real USDG against that token actually names. A stock is a strand only if $1,000 fills within 3% of that price in both directions — a basket you can sell into but not buy out of is half a market.
| Stock | Price | Sell $1k | Buy $1k | Round trip | Pools |
|---|---|---|---|---|---|
| AAPLAAPL Apple | $335.41 | 0.04% | 0.05% | 0.09% | 7 4 v4 |
| GLDGLD SPDR Gold Trust | $399.02 | −0.57% | 0.67% | 0.10% | 6 3 v4 |
| GOOGLGOOGL Alphabet Class A | $350.50 | −0.14% | 0.24% | 0.10% | 5 3 v4 |
| NVDANVDA NVIDIA | $222.46 | 0.15% | −0.05% | 0.10% | 7 5 v4 |
| QQQQQQ Invesco QQQ | $720.42 | −0.15% | 0.25% | 0.10% | 3 1 v4 |
| SGOVSGOV iShares 0-3 Month Treasury Bond | $101.11 | 0.17% | −0.07% | 0.10% | 4 2 v4 |
| SPCXSPCX Space Exploration Technologies Corp. Class A Common Stock | $152.84 | 0.22% | −0.12% | 0.10% | 6 3 v4 |
| SPYSPY SPDR S&P 500 ETF Trust | $761.61 | −0.32% | 0.43% | 0.11% | 4 2 v4 |
| GMEGME GameStop | $22.55 | 0.33% | −0.21% | 0.12% | 6 3 v4 |
| LLYLLY Eli Lilly | $1,151.19 | −0.20% | 0.33% | 0.13% | 8 5 v4 |
| COSTCOST Costco | $897.10 | 0.10% | 0.12% | 0.22% | 4 2 v4 |
| AMCAMC AMC Entertainment | $2.72 | 0.28% | 0.00% | 0.28% | 8 7 v4 |
| RBLXRBLX Roblox | $47.84 | 0.61% | −0.29% | 0.32% | 5 3 v4 |
| USOUSO United States Oil Fund | $154.55 | 0.99% | −0.62% | 0.37% | 3 1 v4 |
| TSLATSLA Tesla | $363.83 | −0.14% | 0.52% | 0.38% | 4 1 v4 |
| PLTRPLTR Palantir Technologies | $177.62 | 0.55% | −0.15% | 0.40% | 3 2 v4 |
| IBMIBM IBM | $230.29 | 0.15% | 0.32% | 0.47% | 7 5 v4 |
| METAMETA Meta Platforms | $666.81 | −0.21% | 0.68% | 0.47% | 3 1 v4 |
| DJTDJT Trump Media & Technology Group | $8.89 | 0.11% | 0.39% | 0.50% | 3 2 v4 |
| BABABABA Alibaba | $113.78 | −0.46% | 0.98% | 0.52% | 5 3 v4 |
| MSFTMSFT Microsoft | $495.86 | 0.46% | 0.10% | 0.56% | 3 2 v4 |
| AMZNAMZN Amazon | $253.88 | 0.12% | 0.47% | 0.59% | 3 2 v4 |
| HIMSHIMS Hims & Hers Health | $28.03 | 0.35% | 0.24% | 0.59% | 5 3 v4 |
| CRCLCRCL Circle Internet Group | $91.77 | 0.24% | 0.37% | 0.61% | 5 4 v4 |
| MUMU Micron Technology | $1,014.50 | 0.64% | −0.03% | 0.61% | 2 1 v4 |
| SLVSLV iShares Silver Trust | $59.86 | −0.13% | 0.75% | 0.62% | 3 |
| TTWOTTWO Take-Two Interactive Software | $207.36 | 0.33% | 0.30% | 0.63% | 5 4 v4 |
| NFLXNFLX Netflix | $72.10 | 0.35% | 0.31% | 0.66% | 4 2 v4 |
| LULULULU Lululemon | $97.63 | 0.33% | 0.34% | 0.67% | 5 3 v4 |
| RIVNRIVN Rivian Automotive | $15.00 | −0.09% | 0.76% | 0.67% | 5 3 v4 |
| MRNAMRNA Moderna | $154.20 | −0.18% | 0.88% | 0.70% | 4 2 v4 |
| INTCINTC Intel | $109.06 | −0.25% | 0.97% | 0.72% | 2 1 v4 |
| USARUSAR USA Rare Earth | $15.61 | 0.32% | 0.43% | 0.75% | 1 |
| AMDAMD AMD | $559.47 | 1.19% | −0.43% | 0.76% | 4 2 v4 |
| RDDTRDDT | $152.28 | 0.51% | 0.27% | 0.78% | 4 2 v4 |
| DELLDELL Dell | $570.77 | 0.21% | 1.08% | 1.29% | 4 3 v4 |
| TSMTSM Taiwan Semiconductor Manufacturing | $434.30 | 1.18% | 0.51% | 1.69% | 7 6 v4 |
| ASMLASML ASML Holding NV | $1,676.76 | 1.33% | 0.50% | 1.83% | 4 2 v4 |
| SNDKSNDK Sandisk Corporation | $1,792.46 | 1.47% | 0.66% | 2.13% | 2 1 v4 |
| COINCOIN Coinbase | $193.93 | 0.71% | 1.52% | 2.23% | 2 2 v4 |
| ORCLORCL Oracle | $147.97 | 2.10% | 0.24% | 2.34% | 1 1 v4 |
| RKLBRKLB Rocket Lab Corporation | $64.62 | 1.85% | 0.69% | 2.54% | 1 1 v4 |
| NBISNBIS Nebius Group | $222.73 | 1.90% | 0.86% | 2.76% | 2 2 v4 |
| EWYEWY iShares MSCI South Korea fund | $180.94 | 1.79% | 1.54% | 3.33% | 4 4 v4 |
At the last scan 11 other tokens were left out, each with its reason: CLSK (a $1,000 sale costs 94.78% against Robinhood's price); CRWV (a $1,000 sale costs 16.78% against Robinhood's price); IONQ (no pool can sell $1,000 of it); MSTR (a $1,000 purchase costs 3.93% against Robinhood's price); RGTI (a $1,000 sale costs 96.61% against Robinhood's price); AVGO (no Robinhood price feed through a USDG market); JNJ (no Robinhood price feed through a USDG market); NET (no Robinhood price feed through a USDG market); NU (no Robinhood price feed through a USDG market); QUBT (no Robinhood price feed through a USDG market); SOUN (no Robinhood price feed through a USDG market).
Skein deploys no contract. Every transaction it builds is a call your own wallet makes to a stock token, to USDG, or to Seaport — which was on this chain long before we were, and over which we hold no privilege of any kind. We take no fee, and the page proves it: a lot that pays anybody but its seller is refused by the reader, on our orders and on strangers' alike.
Every rule a lot obeys, executed at block 67,805,274 as one eth_call each — no contract deployed, nothing sent. Every refusal classified by the error Seaport returned, with the control proving the same call succeeds without the guard.
3 of 3 seeds ran 40 random operations each with every invariant checked after every one, then each seed replayed against deliberately broken copies — each break caught by the invariant named for it.
The order builder, the coil arithmetic and the board reader broken one line at a time — each break caught by the check named for it, after a clean control run.
The real app in a real browser against a fork: a coil built, published, read back off the board by a second wallet, and part of it bought.
Not audited. Seaport has been audited by others; this page's use of it has not been audited by anyone. What it has is the list above, and every number on it is re-derived from data/ on every build — the build fails rather than print a figure nobody computed.
Nothing, until somebody pays. Publishing a lot gives Seaport permission to move exactly what the lot offers, and puts the order on chain. The shares sit in your wallet. When a buyer fills a fraction, Seaport moves that fraction of each stock to them and their dollars to you, in one transaction. Take the lot down and you can revoke the approvals whenever you like.
No. Seaport applies one fraction to every item in the order and reverts unless it divides exactly. There is no path through the contract that delivers some strands and not others.
Then the coil cannot be delivered in full, and the board says so — it reads every strand's balance and allowance and shows how much of the lot is still fillable, and which strand is the limit. Your other shares are not stuck: nothing was ever moved.
Often not — and the page tells you when. For the big names the pools cost almost nothing at any size we measured, and you should use them. A lot earns its keep on thin names and on size: the eight dearest stocks here cost 13.26% through the pools at $25,000, and at $100,000 the pools refuse 11 of the 44 altogether.
You do. Every lot on the board is shown next to what its shares are worth at Robinhood's own feed, as a premium or a discount in basis points, so nobody has to take the number on trust.
Gas, and nothing else. Publishing a 12-strand lot costs $0.15 and filling one costs $0.15, at 0.0660 gwei and ETH at $2,624. Skein takes nothing.
Yes. A bid is the same order the other way round: you offer dollars and ask for the strands, and anyone holding them can fill any fraction. Seaport makes the filler provide the shares, so a bid needs nothing of yours but the dollars.