guide_for_setup_env.md

Newbie guide to setup Cairo environment

This document is shortcut guide for starknet beginner using M1 Mac.

Why we write this guide

We have followed this guide provided by Starkathon Preparing to Work with the StarkNet Hackathon Env..

And found out it assumes that participants already have working python environments. In this guide, we describe a way to setup StarkNet environment for those who have no python envronment.

Setup python environment

There are cases where python versions installed in M1 collide and a problem occurs. Remove Pythons installed by brew and reinstall them.

$ brew list
$ brew uninstall <python version> --ignore-dependencies

Add the following syntax to the bottom of .zshrc.

export LANG="en_US.UTF-8"

Install the python

$ brew install python3

Update pip and then set up a working Cairo virtual environment.

$ CFLAGS=-I`brew --prefix gmp`/include LDFLAGS=-L`brew --prefix gmp`/lib pip3 install ecdsa fastecdsa sympy

Setting up the environment for Cairo

$ python3 -m venv ~/cairo_venv
$ source ~/cairo_venv/bin/activate

1. On Mac, you can use brew:

(cairo_venv) $ brew install gmp

2. Install the cairo-lang python package using:

You have to use 8.5.3 version of marshmallow-dataclass.

(cairo_venv) $ pip3 install marshmallow-dataclass==8.5.3 --force

You have to use 0.8.1 version of cairo-lang.

(cairo_venv) $ pip3 install cairo-lang==0.8.1

Compile and Running a Cairo program

1. Create a file, named test.cairo, with the following lines:

func main():
    [ap] = 1000; ap++
    [ap] = 2000; ap++
    [ap] = [ap - 2] + [ap - 1]; ap++
    ret
end

2. Compile: (make sure all commands are executed in the virtual environment)

(cairo_venv) $ cairo-compile test.cairo --output test_compiled.json

3. Run:

(cairo_venv) $ cairo-run \
  --program=test_compiled.json --print_output \
  --print_info --relocate_prints

4. Run with tracer

You can open the Cairo tracer by providing the --tracer flag to cairo-run. Then open it at http://localhost:8100/.

(cairo_venv) $ cairo-run \
   --program=test_compiled.json --print_output \
   --print_info --relocate_prints --tracer
Number of steps: 4 (originally, 4)
Used memory cells: 11
Register values after execution:
pc = 12
ap = 12
fp = 12

Running tracer on http://localhost:8100/

Now open browser and visit http://localhost:8100 to use tracer.

You can find tracer looks like below.

Congratulation!

Now you have a working Cario environment.