pyee

A rough port of Node.js's EventEmitter to Python with a few tricks of its own

pyee Permissive license MIT Active ★ 429 v14.0.0 released 2026-08-13

Install

pyee on PyPI

pip

pip install pyee

uv

uv add pyee

poetry

poetry add pyee

Package facts

License	MIT (permissive)
Python support	supports the current Python release (>=3.12)
Install friction	low — pure-Python wheel
Runtime dependencies	1 — typing-extensions
Maintenance	actively maintained — 0 days since the last release
Last repo commit	2026-08-13
First released	2011-07-17
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: pyee-14.0.0-py3-none-any.whl

Keywords: events, emitter, node.js, node, eventemitter, event_emitter

Development Status :: 4 - BetaIntended Audience :: DevelopersLicense :: OSI Approved :: MIT LicenseOperating System :: OS IndependentProgramming Language :: PythonProgramming Language :: Python :: 3Programming Language :: Python :: 3.12Programming Language :: Python :: 3.13Programming Language :: Python :: 3.14Topic :: Other/Nonlisted Topic

About pyee

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

pyee

Documentation Status (image)

pyee supplies a EventEmitter object that is similar to the EventEmitter class from Node.js. It also supplies a number of subclasses with added support for async and threaded programming in python, such as async/await.

Docs

Autogenerated API docs, including basic installation directions and examples, can be found at <https://pyee.readthedocs.io>.

License

MIT/X11, see LICENSE.

Read as markdown · JSON record · Source repository · 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

pyee provides an EventEmitter class for Python that mimics Node.js's event-driven architecture, with support for async/await and threaded programming patterns.

Low friction: single lightweight dependency (typing-extensions), pure Python wheel distribution, and actively maintained with a recent release. Repository shows steady engagement with 429 stars and current Python 3.12+ support.

MIT license permits unrestricted use, modification, and distribution in both open-source and commercial projects with minimal obligations—only attribution required.

Usage

pip install pyee
from pyee import EventEmitter
ee = EventEmitter()
@ee.on('event')
def handler(data):
    print(data)
ee.emit('event', 'hello')

Requires Python 3.12 or later; async/await features require an async runtime context.

Verdict: pyee is a well-maintained, low-friction event emitter library suitable for event-driven Python applications. Active development, permissive MIT licensing, minimal dependencies, and no known vulnerabilities make it a reliable choice for projects needing Node.js-style event patterns.

Needs verification

Whether the async/await subclasses require additional setup or configuration beyond the base EventEmitter
Performance characteristics and suitability for high-throughput event scenarios

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