Push notifications published to ntfy.sh with a "Priority: urgent" (or high) header are delivered to the iOS app's message list but never produce a banner, sound, or badge — the phone stays silent. Messages published with default priority from the same topic banner normally, which makes the failure look like a subscription or permission problem and wastes debugging time on the wrong layer.

Getting CPU usage, memory statistics, and disk space information on macOS for a monitoring dashboard, system tray app, or CLI tool. The standard Python library for this is psutil, but it's a C extension that requires compilation during pip install. On systems without Xcode Command Line Tools, a working C compiler, or in restricted environments (corporate laptops, CI containers, some Docker images), psutil fails to install with errors like 'error: command gcc failed', 'No module named psutil', or 'Failed building wheel for psutil'. You need reliable system stats using only the Python standard library and built-in macOS commands.