Toy implementation of FHE algorithms
82 Stars
Updated Last
1 Year Ago
Started In
August 2019

ToyFHE.jl - A toy implementation of FHE algorithms

I frequently hear music in the heart of noise. - George Gershwin

Documentation Build Status


This package currently depends on a number of modifications to upstream packages. The included Manifest.toml lists known working versions for these packages. To use those versions, first clone this package to a location of your choice:

$ git clone ToyFHE

Then load up the project within Julia:

$ julia --project=ToyFHE

If you do not have the correct versions of the dependencies installed, you may be asked to install them via instantiate:

julia> using Pkg

julia> Pkg.instantiate()


julia> cd("ToyFHE/examples/encrypted_mnist")

julia> include("train.jl")

julia> include("infer.jl")


  • DEVELdocumentation of the in-development version.


WARNING: The code in this repository is in an extremely alpha quality. You may want to check back in a little bit once things have been cleaned up.

This repository is a playground for exploring homomorphic encryption protocols. The design goal is ease of use and ease of readability over absolute performance or suitability for production HE applications. The goal of this code is to aid in research and the quick exploration of HE applications.

This package currently contains (partial) implementations of the following HE schemes:

  • Brakerski/Fan-Vercauteren (BFV)
  • Brakerski-Gentry-Vaikuntanathan (BGV)
  • Cheon-Kim-Kim-Song (CKKS)

Both power-of-two and general cyclotomic rings are supported for homomorphic operations. The former is based on a pure Julia FFT implementation and thus likely suitable for multi-threading and GPU applications with little additional effort (those this has not been done so far). The latter is based on the Nemo stack of Julia packages, which are ultimately using FLINT as the execution engine.


Performance notice

This package has not been optimized for performance. The only implementated performance optimizations are those that were absolutely required to perform the desired algorithmic exploration. PRs are welcome to improve performance (as long as readability is preserved), but such work is not currently on the roadmap.

Security Notice

This package currently has known issues (weak RNG, known timing side channels) that make it unsuitable for use other than for algorithmic research. DO NOT USE FOR PRODUCTION APPLICATIONS (I mean it). As with the performance consideration, these issues are addressable, but not currently on the roadmap.


I am not a cryptographer. I am not your cryptographer. This code is a toy. This code is not intended for production use. This code has not been audited or validated. Consult a professional cryptographer, before using cryptography. No warranty (see LICENSE). Don't sue me.