Sill Note
Shutterline construction.
Abstract
Shutterline issues 40,000 SHUT. The whole issue stands on the Quote Lane at launch. The Quote Lane runs on Uniswap v4. The chain is Ethereum. The quote is ETH. No further SHUT is created.
Each trade on the Quote Lane leaves a Slat Cut of two percent. Holding SHUT does not pay the Slat Cut. Sending SHUT from one Slat Owner to another, outside a trade, does not pay the Slat Cut. The Slat Cut is locked at construction.
The Slat Cut gathers while an Open Blind is running. At the start of that Blind a Binding is written. The Binding is a split between two spends: Shelved SHUT, which leaves issue, and Deepen, which returns value into the Quote Lane. The Binding is taken from a block value that nobody selects in advance. The deployer has no path that chooses it. A Slat Owner has no path that chooses it. While the Open Blind runs, the Binding cannot be read. When Blind Timing closes the window, the Binding is shown and the gathered Slat Cut is spent on that split. Blind Timing is locked at construction.
A Slat Owner who watches the chain sees every transfer, every Binding, and every Blind Close. The record is public. Nothing is mixed. Nothing is shielded. A sender remains linked to a recipient. Unpredictability here means that the split is bound before it is known, not that activity is hidden.
The issue is locked at construction. Shelved SHUT is not reissued. The deployer has no path that shifts a Slat Owner’s tokens, pauses the Quote Lane, or mints. If a window gathers no Slat Cut, Blind Close still shows the Binding. Nothing is spent. If a call to close reverts, the Open Blind remains open until a later close succeeds; the Binding does not change.
A Slat Owner verifies the rules on the explorer: the issue reads 40,000 at construction and never rises; the Slat Cut reads two percent and never moves; each Binding is an event with a block; each Blind Close is an event that spends according to that Binding; Shelved SHUT does not return to any balance.
The Sill Note is this document. It states what is fixed. It does not add a date, a team, or a figure that is not in the construction.
The problem, stated once
If a split can be read while a window is still taking fills, anyone can trade into the destination. That turns a fee into a signal. Shutterline answers that behaviour by writing the split first and showing it only when the window ends.
The answer is not concealment. Transfers stay public. The Binding is public after Blind Close. Senders stay linked to recipients.
Design
The token contract holds the issue. The Quote Lane holds the market. Blind Timing opens and closes windows. A Binding is written at open and spent at close. Each part cannot do the others’ jobs: the token cannot pick a Binding; the lane cannot mint; Blind Timing cannot move a balance.
Parameters
| Name | Value | Unit | Where it lives | Setter |
|---|---|---|---|---|
| Issue | 40,000 | SHUT | token contract | none |
| Slat Cut | 2 | % | Quote Lane fee path | none |
| Blind Timing | fixed | rule | construction | none |
| Quote | ETH | asset | Quote Lane | none |
| Venue | Uniswap v4 | venue | Quote Lane | none |
| Chain | Ethereum | chain | Quote Lane | none |
Mechanism
Blind Timing opens a window. A Binding is derived from a block value nobody selects and is written as an event. Trades on the Quote Lane leave a Slat Cut of two percent, which gathers. Blind Timing closes the window. Blind Close shows the Binding and transfers the gathered take: some SHUT is Shelved and leaves issue; the rest Deepens the Quote Lane. Events are emitted for the Binding and for the spend.
Worked examples
| Window | Fills | Unit | Slat Cut gathered | Unit | Spend |
|---|---|---|---|---|---|
| Busy | 10 × 100 | SHUT | 20 | SHUT | Spent on the Binding shown at close |
| Quiet | none | SHUT | none | SHUT | Binding shown; nothing spent |
Failure and edge cases
A window with no trades: Binding is shown, nothing is spent. A close that reverts: the Open Blind remains, the Binding does not change, a later close may succeed. An empty Slat Owner balance: nothing to send, nothing to take. A send that is not a trade: no Slat Cut.
What cannot change
Slat Cut, Blind Timing, and issue are locked at construction. The deployer has no path that shifts a balance, pauses the Quote Lane, or reissues Shelved SHUT. Those fields are construction.
Verification
Issue never rises above 40,000 SHUT. Fee never leaves two percent. Binding events cite a block. Blind Close events spend according to the matching Binding. Shelved SHUT does not return to a balance.
Notation
Slat Cut — two percent of a trade. Open Blind — a window with a written, unread Binding. Binding — the committed split. Blind Close — reveal and spend. Shelved SHUT — units that left issue. Deepen — spend into the Quote Lane. Quote Lane — Uniswap v4, Ethereum chain, ETH quote asset. Slat Owner — a holder of SHUT. Sill Note — this document. Blind Timing — the rule that opens and closes blinds.