Skip to main content

Ccurl PoW Interface for PyOTA

Project description

A python interface to load Ccurl library and perform proof of work locally, without relying on a node. To be used together with PyOTA, the Python Client Library for IOTA. For more info, read the docs.


Currently, PyOTA doesn’t support performing proof of work locally. The attach_to_tangle API command sends the prepared transaction trytes to an IOTA node, that does the PoW by filling out attachment_timestamp* fields and calculating nonce with Curl P-81. In case of bundles, transactions are chained together through their transaction hash.


To use the module, follow the steps: - Clone the repo from GitHub:

$ git clone

  • Make sure you have cmake available on your system. This is a build dependecy for the ccurl library.
  • Build ccurl according to build instructions and put the .so library into the src folder, or run the init script in the main folder to build and initialize:

$ ./

  • Create a vitual environment / activate the one you use for PyOTA.
  • Install th python package from source by running:

$ pip install -e .

How to use?

Once installed, you can use the module to replace attach_to_tangle core api call in PyOTA. Just import the ccurl_interface module from the pow package and you are good to go.

An example code below illustrates how to do PoW for a bundle consisting of two transactions.

Code Example

import iota
from pprint import pprint
from pow import ccurl_interface

# Generate seed
myseed = iota.crypto.types.Seed.random()

# Generate two addresses
addres_generator = iota.crypto.addresses.AddressGenerator(myseed)
addys = addres_generator.get_addresses(1, count=2)

# Preparing transactions
pt = iota.ProposedTransaction(address = iota.Address(addys[0]),
                              tag     = iota.Tag(b'LOCALATTACHINTERFACE99999'),
                              value   = 0)

pt2 = iota.ProposedTransaction(address = iota.Address(addys[1]),
                               tag     = iota.Tag(b'LOCALATTACHINTERFACE99999'),
                               value   = 0)

# Preparing bundle that consists of both transactions prepared in the previous example
pb = iota.ProposedBundle(transactions=[pt2,pt])

# Generate bundle hash

# Declare an api instance
api = iota.Iota("")

# Get tips to be approved by your bundle
gta = api.get_transactions_to_approve(depth=3)

minimum_weight_magnitude = 14 # target is mainnet

# perform PoW locally
bundle_trytes =\

# Broadcast transactions on the Tangle
broadcasted = api.broadcast_and_store(bundle_trytes)

bundle_broadcasted =iota.Bundle.from_tryte_strings(broadcasted['trytes'])

pprint('Local pow broadcasted transactions are:')


Run nosetests to test in current environment. Run tox -v -p all to test in Python 2.7, 3.5, 3.6 and 3.8.

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for PyOTA-PoW, version 1.1.0
Filename, size File type Python version Upload date Hashes
Filename, size PyOTA_PoW-1.1.0-py3-none-any.whl (35.4 kB) File type Wheel Python version py3 Upload date Hashes View
Filename, size PyOTA-PoW-1.1.0.tar.gz (41.7 kB) File type Source Python version None Upload date Hashes View

Supported by

AWS AWS Cloud computing Datadog Datadog Monitoring DigiCert DigiCert EV certificate Facebook / Instagram Facebook / Instagram PSF Sponsor Fastly Fastly CDN Google Google Object Storage and Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Salesforce Salesforce PSF Sponsor Sentry Sentry Error logging StatusPage StatusPage Status page