FHEW is open-source software distributed under the terms of the GNU General Public License. See the file LICENSE for complete details on the licensing of FHEW. The FHEW library is based on the Fully Homorphic Encryption scheme described in the paper "FHE bootstrapping in less than a second" (L. Ducas and D. Micciancio, Cryptology ePrint Archive 2014/816,) and makes use of the FFTW library (the "Fastest Fourier Transform in the West"). Hence the name FHEW, which you may read as the "Fastest Homomorphic Encryption in the West", though the name is more of a reference to FFTW than a claim about performance. The library provides a symmetric encryption scheme to encrypt (and decrypt) single bit messages, supporting the homomorphic evaluation of arbitrary boolean circuits on encrypted data using a public (evaluation) key.
Ducas, L. (2017). FHEW.