Why Rust for Finance?

The problem quant code faces

Quantitative systems must be fast (price thousands of options, process market data) and correct (a use-after-free in a risk engine is a career-limiting bug). Historically teams chose:

What Rust gives you

1. No garbage collector — predictable latency for pricing and order handling
2. No data races (in safe Rust) — shared state is checked at compile time
3. Zero-cost abstractions — iterators and generics often compile to the same code as hand-written loops
4. A strict compiler — many bugs never reach production

Mental model (three ideas)

1. Ownership — every value has one owner; when the owner goes away, the value is freed
2. Borrowing — you can lend data temporarily without giving it away
3. Types as contracts — encode “this order must have a side” or “this parse might fail” in the type system

Hello, quant world

Every executable starts at fn main(). println! is a macro (the ! matters).

Walkthrough example

fn main() {
    let desk = "Equity Derivatives";
    println!("Desk: {}", desk);
    println!("Status: {}", "READY");
}

Desk: Equity Derivatives
Status: READY

The {} is a placeholder filled by later arguments — like formatted logging you’ll use for fills and risk.

Common beginner mistakes

• Forgetting ! on println → “expected function, found macro” style confusion
• Using single quotes for strings ('hello') — strings need "double quotes"; 'A' is a single character
• Expecting Python-style indentation to define blocks — Rust uses { }

Try it

Run the starter, then personalize the output.