📄️ pprof Basics: CPU, Heap, Goroutine, and Mutex Profiling
How to use Go's built-in pprof profiler to identify CPU hotspots, memory allocation sources, goroutine leaks, and mutex contention.
📄️ cgo Overhead: Why Crossing the C Boundary Is Expensive
The real cost of calling C from Go — goroutine pinning, stack switching, and why cgo in hot loops can tank performance.
📄️ Build Tags and module replace: Why Builds Can Silently Change
How Go build constraints filter files, how module replace directives redirect dependencies, and the surprises that follow when neither is obvious.