Bolt is a C++ template library optimized for heterogeneous computing. Bolt is designed to provide high-performance library implementations for common algorithms such as scan, reduce, transform, and sort. The Bolt interface was modeled on the C++ Standard Template Library (STL). Developers familiar with the STL will recognize many of the Bolt APIs and customization techniques. The primary goal of Bolt is to make it easier for developers to utilize the inherent performance and power efficiency benefits of heterogeneous computing. It has interfaces that are easy to use, and has comprehensive documentation for the library routines, memory management, control interfaces, and host/device code sharing.