Portable networking and other low-level I/O, including sockets, timers, hostname resolution, socket iostreams, serial ports, file descriptors and Windows HANDLEs.
C++11-style atomic<>.
Portable HTTP, WebSocket, and network operations using only C++11 and Boost.Asio
Parallel/GPU-computing library
(C++11) Context switching library.
Coroutine library.
(C++11) Coroutine library.
(C++11) Userland threads library.
Shared memory, memory mapped files, process-shared mutexes, condition variables, containers and allocators.
Lockfree data structures.
Message Passing Interface library, for use in distributed-memory parallel application programming.
Portable C++ multi-threading. C++03, C++11, C++14, C++17.