Installation

This page covers everything you need to get multimark installed and working on your system, from prerequisites through verification.

Requirements

Multimark requires Python 3.9 or later and a C compiler available at install time. The CFFI build step compiles the vendored cmark-gfm C library into a shared object that Python loads at runtime.

On most systems, the necessary build tools are already present. If you are working in a minimal container or a fresh virtual machine, you may need to install a compiler toolchain first.

Platform-specific compiler setup

macOS: Install the Xcode command-line tools if you have not already.

xcode-select --install

Ubuntu / Debian:

sudo apt-get install build-essential python3-dev

Windows: Install the Build Tools for Visual Studio. Select the “Desktop development with C++” workload during installation.

Installing from PyPI

The recommended way to install multimark is with pip inside a virtual environment.

python -m pip install multimark

This downloads the source distribution, compiles the C extension, and installs the package. The entire process typically takes a few seconds on modern hardware.

Installing from Source

For development or to get the latest unreleased changes, clone the repository and install in editable mode.

git clone https://github.com/posit-dev/multimark.git
cd multimark
python -m pip install -e ".[dev]"

Editable mode means changes to the Python source files take effect immediately without reinstalling. However, if you modify the C source or the CFFI build script, you need to rebuild.

Verifying the Installation

After installing, confirm that the package loads correctly and reports the expected library version.

import multimark

multimark.cmark_version()

'0.29.0.gfm.13'

If this prints a version string like 0.29.0.gfm.13, the C library was compiled and linked successfully.

Dependencies

Multimark has a single runtime dependency: cffi. The build process also requires cffi (for generating the bindings) and a C compiler. There are no other third-party dependencies at runtime, keeping the installation lightweight and conflict-free.