> For the complete documentation index, see [llms.txt](https://whitepaper.after-bell.uk/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://whitepaper.after-bell.uk/trading-architecture/central-limit-order-book.md). # Central Limit Order Book Describes the order-book model used to match market participants. AFTERBELL uses an off-chain Central Limit Order Book (CLOB) to match trading interest in binary Yes/No outcomes. The CLOB is the trading layer. Smart contracts on Robinhood Chain provide settlement. ``` User → signed order → off-chain CLOB → match → CTFExchange → on-chain settlement → ERC-1155 outcome tokens ``` ### Signed intent, on-chain settlement A user selects a market and signs an order. The source identifies EIP-712 signed orders, which represent authorized trading intent before settlement. The signature step does not require a gas fee. The source does not define the signed payload, priority rules, cancellation process, expiry rules, or replay-protection design. Those details should not be inferred from EIP-712. The CLOB receives signed orders and finds compatible orders. Node.js and WebSocket are the identified off-chain technologies. A valid match proceeds to `CTFExchange`, the identified component for CLOB settlement, EIP-712 signed orders, and batch execution. ### A separate minting path The source also states that the system can mint new paired shares from USDG. It does not specify the minting algorithm or conditions. Conceptually, this is an alternative to matching an order directly against another participant. Smart contracts hold USDG, issue ERC-1155 Yes/No outcome tokens, and settle markets. The CLOB does not settle the final market answer. Resolution occurs later through the stated oracle process. {% hint style="warning" %} This is proposed architecture. Smart contracts are not yet audited, and an audit is planned before mainnet. {% endhint %} --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://whitepaper.after-bell.uk/trading-architecture/central-limit-order-book.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.