# homenc/HElib

HElib is an open-source software library that implements homomorphic encryption. It supports the BGV scheme with bootstrapping and the Approximate Number CKKS scheme. HElib also includes optimizations for efficient homomorphic evaluation, focusing on effective use of ciphertext packing techniques and on the Gentry-Halevi-Smart optimizations.

Repository: https://github.com/homenc/HElib
Canonical: https://ross.abutalabs.com/products/helib
Homepage: https://homenc.github.io/HElib
Language: C++
License: NOASSERTION
License Family: other
Topics: helib, privacy-enhancing-technologies, cryptography, privacy-by-design, encryption-library, encryption, crypto-library, crypto, bgv
Last push: 2024-08-01T20:47:02+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 4898, "days_push": 762, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3249, forks 760 (observed 2026-08-28T04:07:51.915241+00:00)

## What it is
HElib is an open-source C++ library implementing homomorphic encryption, supporting the BGV scheme with bootstrapping and the CKKS approximate-number scheme. It provides low-level HE routines, automatic noise management, ciphertext packing optimizations, and multi-threading, built on the NTL mathematical library.

## Use cases
- perform computations on encrypted data without decrypting it
- implement BGV homomorphic encryption with bootstrapping in C++
- evaluate approximate arithmetic on encrypted numbers with CKKS
- research privacy-preserving computation and encrypted machine learning
- pack many values into a single ciphertext for efficient SIMD-style HE evaluation

## When to choose
- you need a mature, well-documented C++ library for BGV or CKKS homomorphic encryption
- you need low-level control over HE operations, noise management, and ciphertext packing
- you are a researcher or developer building privacy-enhancing technologies on encrypted data

## When to avoid
- you need a high-level API or language bindings outside C++
- you need fully homomorphic encryption with a scheme other than BGV or CKKS
- you need a lightweight dependency-free solution, since HElib requires the NTL library and C++17

## Facets
- artifact type: library
- maturity: stable
- function: cryptography, security, privacy
- domain: security, privacy, developer-tools
- platform: cpp, cross-platform, windows
- tags: homomorphic-encryption, bgv, ckks, fhe, c-plus-plus, ntl, linux, macos

## Member repositories
- homenc/HElib (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:51.915241+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T07:24:26.464656+00:00, confidence not recorded.
  - readme: https://github.com/homenc/HElib (fetched 2026-08-28T04:07:51.915241+00:00, sha 22e153a30084)
  - homepage: https://homenc.github.io/HElib (fetched 2026-08-29T09:36:59.990529+00:00, sha 1fe1589d5090)
- Data as of 2026-08-30T08:39:29.467469+00:00.