Rx
Reactive Extensions (Rx) for Python
What it is and what it does
RxPY is a Python implementation of Reactive Extensions, a library for building programs that handle asynchronous data and events through observable sequences. Instead of polling or callback-based approaches, you represent data streams as Observables and transform them using chainable operators like map, filter, and group_by. The library handles the threading and scheduling complexity, letting you focus on the logic of data transformation.
The package is designed for developers working with event-driven systems, real-time data processing, or any scenario where asynchronous composition matters. It includes over 120 operators and runs on Python 3.6 or above with no external runtime dependencies, making it straightforward to integrate into existing projects.
Use it for:
- Build real-time data pipelines that transform and filter event streams from APIs or message queues
- Implement reactive UI updates or event handlers that respond to user input and system events
- Compose complex asynchronous workflows where multiple data sources need coordinated handling
- Create event-driven microservices that react to incoming messages or state changes
- Handle time-based operations like throttling, debouncing, or windowing of event streams
Worth the install?
AI-flagged interpretation of the facts on this page — verify before relying
RxPY provides a library for composing asynchronous and event-based programs using observable sequences and query operators, allowing developers to represent and manipulate asynchronous data streams in Python.
Yes, if you need reactive programming patterns in Python. RxPY is production-stable, permissively licensed, and has no dependencies. The main consideration is whether observable-based composition fits your use case better than native async/await—RxPY excels at complex event orchestration but adds a learning curve for teams unfamiliar with reactive paradigms.
Install
rx on PyPI
pip
pip install rxuv
uv add rxpoetry
poetry add rxInstalling Rx
Before you install
Low friction installation with no runtime dependencies. Actively maintained with recent commits and a stable production release status, though the latest release was in 2021.
License in practice
MIT License permits commercial and private use with minimal restrictions, making it suitable for most projects without licensing concerns.
Quickstart
pip install rx
import rx
from rx import operators as ops
source = rx.of("Alpha", "Beta", "Gamma")
composed = source.pipe(
ops.map(lambda s: len(s)),
ops.filter(lambda i: i >= 5)
)
composed.subscribe(lambda value: print(value))
Requires Python 3.6 or above.
Verify before relying
- Whether the 1937 days since release reflects a stable mature library or indicates stalled development relative to reactive programming ecosystem changes
- Performance characteristics and scalability limits for high-throughput event streams
- Compatibility with modern async/await patterns versus the observable-based API
Package facts
| License | MIT License (permissive) |
| Python support | supports the current Python release (>=3.6.0) |
| Install friction | low — pure-Python wheel |
| Runtime dependencies | none |
| Maintenance | actively maintained — 1,937 days since the last release |
| Last repo commit | |
| First released | |
| Downloads | 4,712,467/month — #2,249 on PyPI (30-day window, as of 2026-08-14) |
| Known vulnerabilities | none known (OSV.dev, checked 2026-08-14) |
Evidence: Rx-3.2.0-py3-none-any.whl
Tags
More Python Modules packages
Converts domain names between Unicode and…
permissive · top 100 on PyPI
setuptoolsSetuptools is a Python build backend and…
permissive · top 100 on PyPI
PyYAMLPyYAML parses and emits YAML 1.1 data format,…
permissive · top 100 on PyPI
pydanticPydantic validates Python data structures…
permissive · top 100 on PyPI
annotated-typesProvides reusable metadata objects for use with…
permissive · top 100 on PyPI
typing-inspectionProvides runtime tools to inspect and…
permissive · top 100 on PyPI
pyventusPyventus is a Python library for building…
permissive · top 15,000 on PyPI
reactivexRxPY is a library for building asynchronous and…
permissive · top 5,000 on PyPI
aiostreamaiostream provides composable stream operators…
copyleft · top 5,000 on PyPI
influxdb-clientPython client library for querying and writing…
permissive · top 5,000 on PyPI
observableObservable provides a lightweight event system…
permissive · top 15,000 on PyPI
anyioAnyIO provides a unified asynchronous API that…
permissive · top 100 on PyPI
quixstreamsQuix Streams is a Python framework for building…
permissive · top 15,000 on PyPI
eventkiteventkit provides an event-driven framework for…
permissive · top 5,000 on PyPI
reflexReflex is a Python framework for building…
permissive · top 15,000 on PyPI
aeventkitaeventkit provides event-driven data pipelines…
permissive · top 15,000 on PyPI