How to stop a dev server that is still running on a Mac

Coding Published 4 November 2026

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Open Disk, then Monitor, then Ports, find the server in the list and press Stop. The button changes to Stop? in red. Press it a second time on the same row and NotchStar sends the process a normal quit request. It does not force anything.

Steps

Open the notch, choose Disk, then Monitor, then Ports.
Find the row. Use the filter if the list is long. You can type the port, the project name or part of the command.
Check the project folder and the command line. Make sure it is the server you mean. A database or a tool you use should not be on your stop list.
Press Stop. It turns into Stop? in red.
Press it again. A short message says “Asked” followed by the process name “to quit”. If the request could not be sent, it says it could not stop it.
After a few seconds the row should disappear on the next refresh. If it does not, the program is ignoring the request, as a stuck or busy program might.

What Stop sends

Stop sends SIGTERM, the standard polite request. Many dev servers catch it, close their sockets and exit. It cannot be sent to processes owned by another user, because macOS does not allow it, and NotchStar does not ask for administrator rights. It never sends SIGKILL.

If it does not stop

Go back to the terminal where it was started and press Control + C. If the terminal is gone, find the process in Activity Monitor and use its Force Quit, which is a decision for you. NotchStar will not make it.

Limits

Your own processes only.
No force option. That is deliberate.
Two presses on the same row. If you press Stop on one row and then a different row, the confirmation moves.
Unsaved work in the process is lost if the program exits without saving. A dev server usually has none, but check.
Restarts. A process manager or a file watcher may start the server again straight away.
It does not clean up files such as lock files a server left behind.

Check what is using a port first if you only know the port. If your fan is spinning and you do not know why, see finding the busiest process. The Disk page lists the safety rules for the whole tab.

Quick answers.

Is Stop the same as kill -9?

No. It sends SIGTERM, a normal quit request, which a program can handle and clean up from. It never forces a process.

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Why does the button say Stop with a question mark?

The first press asks for confirmation. A second press on the same row sends the request.

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Keep reading.

Disk space, duplicates, apps and cleanup: See free space, find big folders, duplicates and app leftovers, compress media and clean caches from your Mac notch. Everything goes to the Trash.
How to find what is using port 3000 on a Mac: Open the NotchStar Disk tab, Monitor, Ports, then filter by 3000 to see the command, project folder and whether it is local or on the network.
How to see which process is using the most CPU or memory on a Mac: The NotchStar Disk tab, Monitor, Usage shows the five busiest processes by CPU and by memory, refreshed every few seconds. No per app history.
CPU, memory, disk, battery and network: Live CPU, memory, disk, battery and network speed gauges in your Mac notch. Sampling only runs while the tab is open, so it stays light.

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