Zombie dev servers, not open apps, are draining your Mac's memory

MacOS 'out of application memory' warnings are often caused not by visible apps but by orphaned development server processes left running in the background. When developers close a terminal tab instead of pressing Ctrl+C, the underlying server process is never properly terminated and continues consuming RAM and holding ports. Over days of switching between projects, multiple such zombie servers accumulate silently, collectively exhausting system memory. Broad kill commands like 'killall node' are a common but dangerous fix, as they indiscriminately terminate all Node-based processes — including code editors, language servers, and database tools. The safest approach is to always stop processes by their specific process ID rather than by name.