Skip to content
A proxy re-encryption network to empower privacy in decentralized systems.
Branch: master
Clone or download
KPrasch Merge pull request #992 from jMyles/master
Docs bug discovered at EthNewYork.
Latest commit f558e2f May 22, 2019
Type Name Latest commit message Commit time
Failed to load latest commit information.
.circleci Show tests timings in CircleCI May 16, 2019
deploy Update networks.json Mar 9, 2019
dev/docker adds --build to install docs Apr 2, 2019
docs New endpoint name in docs. May 22, 2019
examples Improved API for Character.from_public_bytes(). May 16, 2019
nucypher Bob character control didn't start: s/emitter/emit May 19, 2019
scripts Deploy then stake example script Mar 12, 2019
tests Make changes in Character.from_public_keys() truly backwards-compatible May 16, 2019
.bumpversion.cfg Bump version: 0.1.0-alpha.21 → 0.1.0-alpha.22 Apr 6, 2019
.coveragerc add coveragrc Jun 25, 2018
.coveralls.yml Try on some coveralls Dec 3, 2018
.gitignore Adding pyenv meta to gitignore. Feb 15, 2019 Add Getting Started section, Code of Conduct, and symlink to Contribu… Feb 5, 2019
CONTRIBUTING.rst Add Getting Started section, Code of Conduct, and symlink to Contribu… Feb 5, 2019
LICENSE Relicense to AGPLv3 for more freedom Mar 5, 2019
Pipfile Ensure pyevm alpha39 in Pipfile; Locks remain the unchanged. Apr 6, 2019
Pipfile.lock Update and relock dependencies. Apr 6, 2019 Discord logo in discord badge Apr 9, 2019
dev-requirements.txt Update and relock dependencies. Apr 6, 2019
mypy.ini Tone-down mypy even more Sep 21, 2018
pytest.ini Test results were not captured by CircleCI. Fixed. Jan 4, 2019
readthedocs.yml Include readthedocs.yml Jan 28, 2019
requirements.txt Update and relock dependencies. Apr 6, 2019
setup.cfg Extrapolate more testing steps for CI workflows; Skip publication ste… Dec 6, 2018 Include aafigure package in Pipfile, and docs Mar 27, 2019

A proxy re-encryption network to empower privacy in decentralized systems

pypi pyversions codecov circleci discord Documentation Status license

The NuCypher network facilitates end-to-end encrypted data sharing for distributed apps and protocols. Access permissions are baked into the underlying encryption, and access can only be explicitly granted by the data owner via sharing policies. Consequently, the data owner has ultimate control over access to their data. At no point is the data decrypted nor can the underlying private keys be determined by the NuCypher network.

Under the hood, the NuCypher network uses the Umbral threshold proxy re-encryption scheme to provide cryptographic access control.

How does NuCypher work?

  1. Alice, the data owner, grants access to her encrypted data to anyone she wants by creating a policy and uploading it to the NuCypher network.

  2. Using her policy's public key, any entity can encrypt data on Alice's behalf. This entity could be an IoT device in her car, a collaborator assigned the task of writing data to her policy, or even a third-party creating data that belongs to her – for example, a lab analyzing medical tests. The resulting encrypted data can be uploaded to IPFS, Swarm, S3, or any other storage layer.

  3. A group of Ursulas, which are nodes of the NuCypher network, receive the access policy and stand ready to re-encrypt data in exchange for payment in fees and token rewards. Thanks to the use of proxy re-encryption, Ursulas and the storage layer never have access to Alice's plaintext data.

  4. Bob, a data recipient, sends an access request to the NuCypher network. If Bob was granted an access policy by Alice, the data is re-encrypted for his public key, and he can subsequently decrypt it with his private key.

More detailed information:



"NuCypher - A proxy re-encryption network to empower privacy in decentralized systems"

by Michael Egorov, David Nuñez, and MacLane Wilkison - NuCypher


"NuCypher - Mining & Staking Economics"

by Michael Egorov, MacLane Wilkison - NuCypher


"Umbral: A Threshold Proxy Re-Encryption Scheme"

by David Nuñez

Getting Involved

NuCypher is a community-driven project and we're very open to outside contributions.

All our development discussions happen in our Discord server, where we're happy to answer technical questions, discuss feature requests, and accept bug reports.

If you're interested in contributing code, please check out our Contribution Guide and browse our Open Issues for potential areas to contribute.

Get up and running quickly by using our docker development setup


If you identify vulnerabilities with any nucypher code, please email with relevant information to your findings. We will work with researchers to coordinate vulnerability disclosure between our stakers, partners, and users to ensure successful mitigation of vulnerabilities.

Throughout the reporting process, we expect researchers to honor an embargo period that may vary depending on the severity of the disclosure. This ensures that we have the opportunity to fix any issues, identify further issues (if any), and inform our users.

Sometimes vulnerabilities are of a more sensitive nature and require extra precautions. We are happy to work together to use a more secure medium, such as Signal. Email and we will coordinate a communication channel that we're both comfortable with.

A great place to begin your research is by working on our testnet. Please see our documentation to get started. We ask that you please respect testnet machines and their owners. If you find a vulnerability that you suspect has given you access to a machine against the owner's permission, stop what you're doing and immediately email

You can’t perform that action at this time.