“Port 3000 is already in use” — fixed from ⌘K
Every listening TCP port on your Mac, the process holding it, and a way to kill it — in Notchy's command palette, instead of another round of copying a pid out of lsof.
Port, process, pid
The three things you actually wanted from that command, as rows you can read. Type the port number in ⌘K and it is there.
Kill it and move on
The stale server from the last branch stops where you found it — SIGTERM, the same signal Ctrl-C sends, so it shuts down properly. No terminal tab, no pid pasted into a second command, no accidental kill of the wrong one.
Uses lsof, on purpose
No privileged helper and no root: the same unprivileged tool you would have run, parsed properly. Both the IPv4 and IPv6 binding of a forked server show up rather than one being silently swallowed.
Part of a dev-shaped notch
Next to a real terminal in the island, long-command alerts, PR and CI status and Claude Code approvals.
Everything Notchy does, for free
- Fluid Dynamic Island animations on the Mac notch
- Command palette (⌃⌥K) — every action one keystroke away
- Knock — double-tap a modifier key to open the notch
- AI usage tracker (Claude Code, Codex, Cursor, Copilot)
- Detach any tab into a menu-bar popover
- Now Playing music controls (Apple Music & Spotify)
- Time-synced karaoke lyrics under the notch
- Mac clipboard history shelf (password-manager safe)
- Searchable clipboard — filter by text, file name, or OCR'd words
- On-device OCR — copy a screenshot, get its text (Apple Vision)
- Window snapping — drag a window to the notch to tile it
- App Launcher — pin apps to the notch, open with one tap
- Text snippets — TextExpander-style pastes from the ⌘K palette
- One-tap screen capture to clipboard + shelf
- Color eyedropper — sample any pixel, hex auto-copied
- System-wide mic mute for every meeting app at once
- Keystroke HUD for demos & screencasts (secure-input safe)
- Keyboard cleaning lock with countdown island (⌘⎋ unlocks)
- Menu-bar icon hiding — Bartender-style separator & chevron
- Live CPU / memory / network stats flyout
- Open GitHub PR count in the notch (Keychain-stored token)
- iPhone-style call island — Answer/Decline FaceTime on the notch
- Notch Terminal — real VT100/xterm shell in a PTY, its own tab
- Privacy Indicator — pill when any app's camera or mic goes live
- Caps Lock HUD — brief island on every toggle
- Full Charge island with adjustable threshold + low-battery sound
- Alt HUD styles — edge-pinned bar or circular gauge off the notch
- Audio-reactive Now Playing visualizer (real FFT of system audio)
- Custom closed-notch idle animation — drop in your own Lottie JSON
- Drag-and-drop file drop shelf — persists across relaunches
- Zip & unzip files right from the shelf
- Image converter (HEIC, PNG, JPEG, TIFF, PDF) + video → GIF
- Run Apple Shortcuts with one tap
- Screenshots auto-staged on the shelf, ready to drag
- Download finished alerts with Reveal in Finder
- USB drive mount island with one-tap Eject
- Apple Reminders quick capture & due list
- macOS Pomodoro notch timer & stopwatch — streaks + 7-day chart
- Resizable expanded panel (width & height, live preview)
- System HUDs (volume, brightness, battery)
- Audio output switcher (speakers, AirPods, monitor)
- AirPods connection manager & battery
- Magic Mouse, Keyboard & Trackpad battery + low-battery alerts
- Quick notes & Calendar widgets
- Camera Mirror (check your appearance)
- Keep Awake (caffeine toggle)
- Teleprompter (Cuely) for Zoom calls
- Focus-aware alerts & native haptic feedback
- Lock screen widgets & hide-the-notch mode
- 133 languages, fully localized
- Native SwiftUI, tuned for Apple Silicon
Ports on macOS — FAQ
How do I find what is using a port on macOS?
The command is lsof -nP -iTCP -sTCP:LISTEN, and then you read pids out of a wall of text. Notchy runs that for you and shows a list: port, process name and pid, searchable from the ⌘K command palette.
Can I kill the process from there?
Yes. Find the port, stop the process holding it, go back to your dev server — the whole loop without a terminal or a pasted pid. It sends SIGTERM, the same signal Ctrl-C does, so the server gets to shut down cleanly rather than being killed outright.
Does it need root or a helper tool?
No. It shells out to lsof exactly as you would, which is happy unprivileged — the syscall alternative would need root to see processes you do not own, so the tool you would have typed is the right one.
Why does one port show twice?
A forked server that binds both IPv4 and IPv6 legitimately holds the same port under more than one pid. The list is deduplicated by pid and port together, so both rows are real rather than a display bug.
Is it a network monitor?
No. It lists listening TCP sockets — what is bound, and by whom. Throughput and Wi-Fi details live on the system and network cards instead.
Is it free?
Yes. Notchy is free with no trial, licence key or subscription, on macOS 13 Ventura and later.