jupyter-client

Jupyter protocol implementation and client libraries

jupyter-client Permissive license BSD 3-Clause License - Copyright (c) 2001-2015, IPython Development Team - Copyright (c) 2015-, Jupyter Development Team All rights reserved. Redistribution and use in source and binary forms, with… (full text in the JSON record) Active ★ 471 v8.9.1 released 2026-06-09

Install

jupyter-client on PyPI

pip

pip install jupyter-client

uv

uv add jupyter-client

poetry

poetry add jupyter-client

Package facts

License	BSD 3-Clause License - Copyright (c) 2001-2015, IPython Development Team - Copyright (c) 2015-, Jupyter Development Team All rights reserved. Redistribution and use in source and binary forms, with… (full text in the JSON record) (permissive)
Python support	supports the current Python release (>=3.10)
Install friction	low — pure-Python wheel
Runtime dependencies	6 — jupyter-core, python-dateutil, pyzmq, tornado, traitlets, typing-extensions
Maintenance	actively maintained — 65 days since the last release
Last repo commit	2026-06-12
First released	2015-07-12
Popularity	one of the top 1,000 most-downloaded packages on PyPI (30-day window, as of 2026-08-13)
Known vulnerabilities	none known (OSV.dev, checked 2026-08-13)

Evidence: jupyter_client-8.9.1-py3-none-any.whl

Keywords: Interactive, Interpreter, Shell, Web

Framework :: JupyterIntended Audience :: DevelopersIntended Audience :: EducationIntended Audience :: Science/ResearchIntended Audience :: System AdministratorsLicense :: OSI Approved :: BSD LicenseOperating System :: OS IndependentProgramming Language :: PythonProgramming Language :: Python :: 3

About jupyter-client

from the package's own PyPI description — quoted content, verbatim

Jupyter Client

Build Status (image) Documentation Status (image)

jupyter_client contains the reference implementation of the [Jupyter protocol]. It also provides client and kernel management APIs for working with kernels.

It also provides the jupyter kernelspec entrypoint for installing kernelspecs for use with Jupyter frontends.

Development Setup

The Jupyter Contributor Guides provide extensive information on contributing code or documentation to Jupyter projects. The limited instructions below for setting up a development environment are for your convenience.

Coding

You'll need Python and pip on the search path. Clone the Jupyter Client git repository to your computer, for example in /my/project/jupyter_client

cd /my/projects/
git clone git@github.com:jupyter/jupyter_client.git

Now create an [editable...

Read as markdown · JSON record · Source repository · Homepage · Docs

AI interpretation — verify before relying

AI-generated interpretation of the package facts above; every digit, version, license, or vulnerability id it cites is grounded in the facts already shown on this page

jupyter-client implements the Jupyter protocol and provides APIs for managing kernel lifecycle and communication, plus the `jupyter kernelspec` command for installing kernel specifications.

Low friction: pure Python wheel with six stable runtime dependencies (jupyter-core, python-dateutil, pyzmq, tornado, traitlets, typing-extensions). Active maintenance with a release 65 days ago and ongoing commits.

BSD 3-Clause (permissive): you may use, modify, and distribute this package freely in commercial and private projects, provided you retain the copyright notice and disclaimer.

Usage

pip install jupyter-client==8.9.1

from jupyter_client.kernelspec import KernelSpecManager
manager = KernelSpecManager()
kernels = manager.get_all_specs()

Requires Python >=3.10; pyzmq may require a C compiler on some platforms.

Verdict: Stable, actively maintained core Jupyter infrastructure with no known vulnerabilities. Low install friction, permissive license, and top-1000 popularity make it a reliable choice for applications needing kernel management or Jupyter protocol support.

Needs verification

Whether pyzmq's C extension compilation is automatic or requires manual setup on Windows/macOS systems.
Performance characteristics under high-concurrency kernel management scenarios.

jupyter kernel managementjupyter protocol implementationkernel client libraryjupyter kernelspec installerjupyter frontend communicationipython kernel control