We are excited to present wzprof: a pprof-based profiler for WebAssembly modules. With it we can collect CPU and memory profiles during their execution. You execute your program compiled to WebAssembly under wzprof, and you get profiling metrics that can be consumed by anything that understands the pprof format (e.g. go pprof, Pyroscope, Parca).

A few things motivated us to build this tool. WebAssembly runtimes typically allow profiling guest code via an external profiler such as perf, but in many cases, the recording and analysis of profiles remain a difficult task, especially due to features like JIT compilation. pprof is the de-facto standard profiling tool for Go programs and offers some of the simplest and quickest ways to gather insight into the performance of an application. wzprof aims the combine the capabilities and user experience of pprof, enabling the profiling of any application compiled to WebAssembly.