HPX is an open-source, modern asynchronous many-task (AMT) runtime system designed to tackle the scalability and resource utilization challenges of large-scale distributed computing. Built to extend the C++ Standard Library, HPX unifies the syntax and semantics of local and remote operations, enabling developers to write portable, scalable applications with familiar C++ syntax.

HPX leverages C++ futures and coroutines to enable seamless overlap of computation and communication, optimizing system utilization with minimal overhead. Its threading subsystem implements lightweight user-level threads that support rapid context switching, minimizing synchronization delays and enhancing parallel efficiency. With its Active Global Address Space (AGAS), HPX facilitates flexible object migration and load balancing across distributed environments. Its parcel transport layer supports asynchronous communication and integrates with multiple communication interfaces, such as MPI and LCI. Furthermore, HPX offers interoperability with a wide range of accelerators and performance portability libraries, making it versatile for diverse high-performance computing needs. Finally, HPX resiliency APIs provide fault tolerance and error recovery, enhancing the reliability of distributed applications. Together, these features make HPX a powerful, portable tool for developing high-performance, scalable applications.