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Project Description

collection of modules to build distributed and reliable concurrent systems in Python.


  • Python from 2.6 to 3.x
  • A platform supported by libuv <>

Simple example

A simple example showing how to create a consumer and use other actor function to feed it.

import flower

messages = []
sources = []
def consumer():
    # wait for coming message in the current actor
    while True:
        source, msg = flower.receive()
        if not msg:
        print("got message from %s: %s" % (source.ref, msg))

def publisher1(ref):
    # an actor sending messages to the consumer
    msg = ['hello', 'world']
    for s in msg:
        flower.send(ref, s)

def publisher2(ref):
    msg = ['brave', 'new', 'world', '']
    for s in msg:
        flower.send(ref, s)

ref_consumer = flower.spawn(consumer)
flower.spawn(publisher1, ref_consumer)
flower.spawn(publisher2, ref_consumer)

should return:

$ python examples/
got message from 1: hello
got message from 2: brave
got message from 1: world
got message from 2: new
got message from 2: world


Flower requires Python superior to 2.6 (yes Python 3 is supported)

To install flower using pip you must make sure you have a recent version of distribute installed:

$ curl -O
$ sudo python
$ easy_install pip

For now flower can only be installed from sources. To install or upgrade to the latest released version of flower:

$ git clone
$ cd flower && pip install -r requirements.txt


flower is available in the public domain (see UNLICENSE). flower is also optionally available under the MIT License (see LICENSE), meant especially for jurisdictions that do not recognize public domain works.

Release History

Release History


This version

History Node

TODO: Figure out how to actually get changelog content.

Changelog content for this version goes here.

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