There is some output (slop) I got from my recent sessions (yes, yes, I am guilty and ashamed):
### Validation Summary I have verified the implementation across the **Functional Core** (Domain) and the **Imperative Shell** (Infrastructure & Interface), confirming that the code doesn't just "look" right but functionally enforces the rules. **1. Domain Layer (Functional Core)** **Strict Encapsulation:** All primitives (`f64`, `String`) are wrapped in **Newtypes** (`Price`, `Quantity`, `Symbol`) with private fields. **Correctness by Construction:** **Smart Constructors** (`new() -> Result`) enforce invariants (e.g., price > 0, symbol format). It is impossible to instantiate invalid domain objects. **Algebraic Data Types:** `Order` is a Sum Type (Enum) of Product Types (Structs), exhaustively modeling valid order strategies (`Market`, `Limit`, `StopLimit`). **Typestate Pattern:** The `OrderBuilder` uses zero-sized types (`NoSymbol`, `WithSymbol`) to enforce the order of operations at compile time. You cannot build an order without mandatory fields. **Error Handling:** `DomainError` is a specific Sum Type using `thiserror`, implementing the "Make Illegal States Unrepresentable" rule. **2. Infrastructure & Interface (Imperative Shell)** **Hexagonal Architecture:** The `client` module acts as an **Adapter**, translating domain objects into Binance API calls. It isolates side effects (I/O, Time, Crypto). **Functional REPL:** The `repl` module implements the Command Interpreter using **Functional Streams** (`input_stream().map().for_each()`), strictly avoiding imperative `while` loops. **Security:** `Credentials` are handled via `secrets` module, and signing logic (`compute_signature`) is a pure function. **3. Verification (Tests)** **Pass Rate:** **124/124 tests passed**. **Coverage:** The test suite is organized into "Stories" (e.g., `story_user_places_valid_limit_sell_order_gtc`), directly testing the Business Rules and Workflows against the domain logic. The project is correctly set up as a mathematically rigorous, type-driven trading assistant. here is another one:
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