#fhe #bfv #lattice #cryptography


A Fully Homomorphic Encryption (FHE) compiler supporting the Brakerski/Fan-Vercauteren (BFV) scheme

3 unstable releases

Uses new Rust 2021

0.6.1 Jul 14, 2022
0.6.0 Jul 14, 2022
0.5.0 May 17, 2022

#374 in Cryptography


258K SLoC

C++ 102K SLoC // 0.1% comments C 93K SLoC // 0.2% comments Visual Studio Project 21K SLoC C# 14K SLoC // 0.3% comments Python 10K SLoC // 0.3% comments Rust 9K SLoC // 0.2% comments Shell 3K SLoC // 0.2% comments Ada 1.5K SLoC // 0.2% comments GNU Style Assembly 1.5K SLoC // 0.3% comments Assembly 1.5K SLoC // 0.2% comments Pascal 1K SLoC // 0.2% comments Visual Studio Solution 878 SLoC Batch 169 SLoC Prolog 161 SLoC Lua 68 SLoC // 0.0% comments Automake 33 SLoC


Sunscreen is an ecosystem for building privacy-preserving applications using fully homomorphic encryption.

This project is licensed under the terms of the GNU AGPLv3 license. If you require a different license for your application, please reach out to us.

WARNING! This library is meant for experiments only. It has not been externally audited and is not intended for use in production.


Below, we look at how to multiply two encrypted integers together.

use sunscreen::{
    types::{bfv::Signed, Cipher},
    Compiler, Error, Runtime,

#[fhe_program(scheme = "bfv")]
fn simple_multiply(a: Cipher<Signed>, b: Cipher<Signed>) -> Cipher<Signed> {
    a * b

fn main() -> Result<(), Error> {
    let app = Compiler::new()

    let runtime = Runtime::new(app.params())?;

    let (public_key, private_key) = runtime.generate_keys()?;

    let a = runtime.encrypt(Signed::from(15), &public_key)?;
    let b = runtime.encrypt(Signed::from(5), &public_key)?;

    let results = runtime.run(app.get_program(simple_multiply).unwrap(), vec![a, b], &public_key)?;

    let c: Signed = runtime.decrypt(&results[0], &private_key)?;

    assert_eq!(c, 75.into());



Getting help

For questions about Sunscreen, join our Discord!


~203K SLoC