Getting started

1. Requirements

Needed	Version	Check
Python	3.10 or newer	python3 --version
Rust	any recent stable	rustc --version
C linker	system default	installed with the steps below
NumPy	optional, for arrays	pip install "pyrust-engine[arrays]"

Without Rust everything still runs correctly as plain Python, and PyRust shows one warning with the exact fix.

2. Install Rust

macOSLinuxWindows

xcode-select --install          # C linker, skip if already installed
brew install rustup && rustup default stable

sudo apt install build-essential    # Fedora: sudo dnf install gcc
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

Install Visual Studio Build Tools with "Desktop development with C++", then run winget install Rustlang.Rustup.

3. Install PyRust Engine

pip install "pyrust-engine[arrays]"
python -m pyrust_engine doctor

doctor checks Python, Rust, the linker and NumPy, and compiles a test function.

4. Speed up a function

from pyrust_engine import optimize

@optimize
def collatz_steps(limit: int) -> int:
    longest = 0
    for start in range(1, limit):
        n, steps = start, 0
        while n != 1:
            n = n // 2 if n % 2 == 0 else 3 * n + 1
            steps += 1
        longest = max(longest, steps)
    return longest

collatz_steps(1_000_000)
print(collatz_steps.explain())

The first call compiles the function (about 0.1–0.4 s, cached on disk afterwards). Later calls run natively.

5. Methods work too

from dataclasses import dataclass

@dataclass
class Account:
    balance: float
    rate: float

    @optimize
    def grow(self, years: int) -> float:
        for _ in range(years):
            self.balance += self.balance * self.rate   # written back to the object after the call
        return self.balance

6. Let the tools find what to speed up

python -m pyrust_engine suggest app.py          # which functions and methods compile, and what blocks the rest
python -m pyrust_engine apply app.py --write    # add @optimize where it compiles and helps

7. In Jupyter

%load_ext pyrust_engine
%pyrust_check collatz_steps
%pyrust_benchmark collatz_steps(100_000)