One of the functionalities missing in WebAssembly for a long time was the ability to spawn new threads within the process. Various runtimes made efforts to address this limitation by introducing non-standard APIs for thread creation. WAMR provides a WAMR pthread library that implements a wide range of pthread APIs, (including synchronization primitives, pthread_create() function and many more). In 2022, the introduction of the WASI threads proposal aimed to establish a standardized API for thread creation in WebAssembly.