Installation

Prerequisites

meridian-tools requires Python 3.11 or later and a working installation of Google Meridian with schema support.

Install Meridian first

Meridian is the upstream modelling engine. Install it before meridian-tools:

pip install "google-meridian[schema]==1.5.3"

If you are working from a local Meridian checkout:

pip install -e "/path/to/meridian[schema]"

Verify the install:

from meridian import version
print(version.__version__)

Install meridian-tools

From the source tree (recommended for development)

cd /path/to/meridian-tools
pip install -e ".[dev]"

The [dev] extra installs pytest, ruff, and mypy for running the test suite and linter.

Editable install without dev extras

pip install -e .

Verify the install

meridian-tools --help

You should see the CLI help output listing the run and demo subcommands. This command is deliberately lightweight — it does not import TensorFlow, NumPy, or Meridian.

You can also verify in Python:

import meridian_tools
print(meridian_tools.__version__)

Runtime dependencies

The following are declared in pyproject.toml and installed automatically:

Package	Version bound
`google-meridian[schema]`	`==1.5.3`
`arviz`	`>=0.18.0, <0.20.0`
`pandas`	`>=2.2.0, <3`
`pydantic`	`>=2.8.0, <3`
`PyYAML`	`>=6.0.0, <7`
`vl-convert-python`	`>=1.7.0, <2`

TensorFlow is not a direct dependency of meridian-tools. It comes transitively through google-meridian.

Development extras

pip install -e ".[dev]"

This adds:

Package	Purpose
`pytest`	Test runner
`ruff`	Linter and formatter

Troubleshooting

If meridian-tools --help fails with an import error, check that:

You are in the correct virtual environment.
Meridian is installed with the [schema] extra.
Python version is 3.11 or later: python --version.

If pip install -e . fails, ensure setuptools>=68.0.0 is available:

pip install --upgrade setuptools

See the troubleshooting guide for more common issues.