CuPy is an open-source library which has NumPy-compatible API and brings high performance in N-dimensional array computation with utilizing Nvidia GPU. Its API is to designed to provide high compatibility with NumPy so that in most cases you can gain several times speed improvement from drop-in replacement to your code. CuPy is actively developed and is continuously well-maintained, resulting in 2,700+ GitHub stars and 13,000+ commits. CuPy was also presented at PyCon 2018