In this talk, we'll explore building a profiler utilizing wasmtime. Initially, we'll demystify the role of profilers, specifically sampling profilers, and their modus operandi. Subsequently, we'll delve into the construction one such profiler, examining epoch interrupts for program interruption and wasmtime's sampling capabilities. Lastly, we'll investigate universal profilers, their utility in understanding multilingual code, and our potential to build one. Come join us as we tread the boundary of profiling and performance optimization in the diverse world of coding.