Contributing

Thank you for your interest in contributing! We welcome all contributions no matter their size. Please read along to learn how to get started. If you get stuck, feel free to ask for help in Libp2p Discover Server.

Setting the stage

To get started, fork the repository to your own GitHub account, then clone it to your development machine:

git clone git@github.com:your-github-username/py-libp2p.git

Next, install the development dependencies and set up the project. We recommend using a virtual environment, such as virtualenv or Python’s built-in venv module. Instructions vary by platform:

Note

py-libp2p contributor setup is currently supported on Python versions <= 3.13.

Linux Setup

Prerequisites

On Debian Linux, you need to install the following dependencies:

Install them with:

sudo apt-get install cmake pkg-config libgmp-dev

Setup Steps

Install the development dependencies using a virtual environment:

Option 1: Using the setup script (recommended):

cd py-libp2p
./scripts/setup_dev.sh

Note

On Linux, if you are not already in a virtual environment, the script will create one automatically and instruct you to activate it.

Option 2: Using uv (recommended, same as CI):

First, install uv if you haven’t already:

curl -LsSf https://astral.sh/uv/install.sh | sh

Or using pip:

pip install uv

Then set up the development environment:

cd py-libp2p
uv sync --group dev
uv run pre-commit install

Option 3: Manual setup with pip:

cd py-libp2p
python3 -m venv .venv
. .venv/bin/activate
pip install --upgrade pip  # Ensure pip >= 25.1 for PEP 735 support
pip install --group dev -e .
pre-commit install

Note: This project uses PEP 735 [dependency-groups] which requires pip >= 25.1. If you have an older pip version, upgrade it first.

An alternative using virtualenv:

cd py-libp2p
virtualenv -p python .venv
. .venv/bin/activate
pip install --upgrade pip  # Ensure pip >= 25.1 for PEP 735 support
pip install --group dev -e .
pre-commit install

macOS Setup

Prerequisites

On macOS, you need to install the following dependencies:

Install them with:

brew install cmake pkgconfig gmp

Setup Steps

Install the development dependencies using a virtual environment:

Option 1: Using the setup script (recommended):

cd py-libp2p
./scripts/setup_dev.sh

Option 2: Using uv (recommended, same as CI):

First, install uv if you haven’t already:

curl -LsSf https://astral.sh/uv/install.sh | sh

Or using Homebrew:

brew install uv

Or using pip:

pip install uv

Then set up the development environment:

cd py-libp2p
CFLAGS="$(pkg-config --cflags gmp)" LDFLAGS="$(pkg-config --libs gmp)" uv sync --group dev
uv run pre-commit install

Option 3: Manual setup with pip:

cd py-libp2p
python3 -m venv .venv
. .venv/bin/activate
pip install --upgrade pip  # Ensure pip >= 25.1 for PEP 735 support
CFLAGS="$(pkg-config --cflags gmp)" LDFLAGS="$(pkg-config --libs gmp)" pip install --group dev -e .
pre-commit install

Note: This project uses PEP 735 [dependency-groups] which requires pip >= 25.1. If you have an older pip version, upgrade it first.

An alternative using virtualenv:

cd py-libp2p
virtualenv -p python .venv
. .venv/bin/activate
pip install --upgrade pip  # Ensure pip >= 25.1 for PEP 735 support
pip install --group dev -e .
pre-commit install

Windows Development Setup

Prerequisites

Python 3.11+ - Download and install Python from python.org or the Microsoft Store. - Verify installation:
```
python --version
```
Git - Install Git using Windows Package Manager (winget) or download from git-scm.com. - Verify:
```
winget install --id Git.Git -e
git --version
```
CMake - Install CMake with winget or download from cmake.org. - Add CMake to your PATH during installation, then verify:
```
winget install --id Kitware.CMake -e
cmake --version
```
Make
- Option 1: Use Git Bash (included with Git) as a shell.
- Option 2: Install make via Chocolatey (install Chocolatey first if needed: choco.io).
- Verify installation:
```
choco install make
make --version
```

Setup Steps

Clone the Repository - Open PowerShell or Git Bash and run:

git clone git@github.com:your-github-username/py-libp2p.git
cd py-libp2p

Create a Virtual Environment - In PowerShell:

python -m venv venv
.\venv\Scripts\activate

Install Dependencies

Option A: Using uv (recommended, same as CI):

First, install uv if you haven’t already:
```
# Using pip
pip install uv

# Or using winget
winget install --id=astral-sh.uv
```
Then set up the development environment:
```
uv sync --group dev
uv run pre-commit install
```
Option B: Using pip:
```
pip install --upgrade pip  # Ensure pip >= 25.1 for PEP 735 support
pip install --group dev -e .
pre-commit install
```
Note: This project uses PEP 735 [dependency-groups] which requires pip >= 25.1. If you have an older pip version, upgrade it first.
Verify Setup - Run the tests to ensure everything works:
```
pytest -v
```
- If using make test with Git Bash:
```
make test
```

Notes

Use PowerShell, Command Prompt, or Git Bash as your shell.
Ensure all tools (Python, Git, CMake) are in your system PATH.

Requirements

The protobuf description in this repository was generated by protoc at version 30.1.

Running the tests

A great way to explore the code base is to run the tests.

We can run all tests with:

make test

Code Style

We use pre-commit to enforce a consistent code style across the library. This tool runs automatically with every commit, but you can also run it manually with:

make lint

If you need to make a commit that skips the pre-commit checks, you can do so with git commit --no-verify.

This library uses type hints, which are enforced by the mypy tool (part of the pre-commit checks). All new code is required to land with type hints, with the exception of code within the tests directory.

Path handling

Use the cross-platform path utilities in libp2p.utils.paths instead of os.path or hard-coded separators. Prefer join_paths() over os.path.join(), get_script_dir(__file__) over os.path.dirname(__file__), and create_temp_file() or get_temp_dir() over hard-coded /tmp/ or C:\\. This keeps the codebase working on Windows, macOS, and Linux. Run python scripts/audit_paths.py to check for path issues; the same audit runs in pre-commit and fails on P0/P1 issues.

For the full API reference, see libp2p.utils.paths. A working example is available in Path Handling Demo.

Documentation

Good documentation will lead to quicker adoption and happier users. Please check out our guide on how to create documentation for the Python Ethereum ecosystem.

Adding Examples

To add a new example (e.g., identify):

Create a directory in examples/identify
Create a file examples/identify/identify.py with the example code
Add __init__.py to make it a proper Python package (automatically discovered by find_packages() in setup.py)
Add the example in the example list docs/examples.rst
Add example tests in tests/core/examples/test_examples.py
Add the example documentation in docs/examples.identify.rst
Add a news fragment for the new release in file newsfragments/536.feature.rst (fix-id.type.rst)
Generate doc files with make docs or make linux-docs in linux (generates files libp2p.identity.identify.rst libp2p.identity.rst libp2p.identity.identify.pb.rst)

Add the example to setup.py:

entry_points={
    "console_scripts": [
        "chat-demo=examples.chat.chat:main",
        "echo-demo=examples.echo.echo:main",
        "ping-demo=examples.ping.ping:main",
        "identify-demo=examples.identify.identify:main",
        "circuit-relay-demo=examples.circuit_relay.relay_example:main"
    ],
}

Run make package-test to test the release:

.....
Activate with ``source <temp-dir>/package-smoke-test/bin/activate``
(The exact path is shown by the script; use that path.)
Press enter when the test has completed. The directory will be deleted.

Then test the example:

source <temp-dir>/package-smoke-test/bin/activate
(package-smoke-test) $ identify-demo

Pull Requests

It’s a good idea to make pull requests early on. A pull request represents the start of a discussion, and doesn’t necessarily need to be the final, finished submission.

GitHub’s documentation for working on pull requests is available here.

Once you’ve made a pull request, take a look at the Circle CI build status in the GitHub interface and make sure all tests are passing. In general pull requests that do not pass the CI build yet won’t get reviewed unless explicitly requested.

If the pull request introduces changes that should be reflected in the release notes, please add a newsfragment file as explained here.

If possible, the change to the release notes file should be included in the commit that introduces the feature or bugfix.

Releasing

Releases are typically done from the main branch, except when releasing a beta (in which case the beta is released from main, and the previous stable branch is released from said branch).

Final test before each release

Before releasing a new version, build and test the package that will be released:

git checkout main && git pull
make package-test

This will build the package and install it in a temporary virtual environment. Follow the instructions to activate the venv and test whatever you think is important.

You can also preview the release notes:

towncrier --draft

Build the release notes

Before bumping the version number, build the release notes. You must include the part of the version to bump (see below), which changes how the version number will show in the release notes.

make notes bump=$$VERSION_PART_TO_BUMP$$

If there are any errors, be sure to re-run make notes until it works.

Push the release to github & pypi

After confirming that the release package looks okay, release a new version:

make release bump=$$VERSION_PART_TO_BUMP$$

This command will:

Bump the version number as specified in .pyproject.toml and setup.py.
Create a git commit and tag for the new version.
Build the package.
Push the commit and tag to github.
Push the new package files to pypi.

Which version part to bump

$$VERSION_PART_TO_BUMP$$ must be one of: major, minor, patch, stage, or devnum.

The version format for this repo is {major}.{minor}.{patch} for stable, and {major}.{minor}.{patch}-{stage}.{devnum} for unstable (stage can be alpha or beta).

If you are in a beta version, make release bump=stage will switch to a stable.

To issue an unstable version when the current version is stable, specify the new version explicitly, like make release bump="--new-version 4.0.0-alpha.1"

You can see what the result of bumping any particular version part would be with bump-my-version show-bump