v0.8.22

New in 0.8.22

• Rows on fire turn red: a process that is hot or flagged gets a red row, so it stands out in the list.
• Who is making the CPU busy: from 30% load, the CPU panel on Overview shows the top two apps and their share, in the same colours as the donut.
• Power in and out: Overview and Energy show what the charger delivers, what the Mac is using, and whether the battery is gaining or losing. A charger too small for the load is called out, with when the battery will run out.
• The screen's power: Power by part adds the display engine, plus the screen's brightness and how hard the backlight is working.
• Update banner can be closed: the ✕ hides it until the next version. Settings still offers Install.

Install / update

Already installed: click Install and relaunch when the update notice appears, or run ~/install-system-sentinel.sh.

New install: download the zip, unzip, move System Sentinel.app to Applications, then run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.

v0.8.21

New in 0.8.21

• CPU and GPU panels on Overview. Each has its own dial, watts, and 1 min / 15 min / 1 hour averages. The GPU panel names the chip and the app using it most. Local AI models show here, not on the CPU.
• GPU colours the menu bar icon. Amber when the graphics chip averages 60% over a minute, red at 90%.
• Power by part (Energy tab). Watts for the CPU, graphics chip, Neural Engine and memory, read from the chip itself with no password, plus the rest of the Mac. Apple silicon only.
• Save power on the Graphics card. Graphics watts now, and one-click ways to cut them: optimise the screen, close a drawing browser tab, unload a local AI model, quit a background app using the GPU, or Low Power Mode on battery.

Install / update

Already installed: click Install and relaunch when the update notice appears, or run ~/install-system-sentinel.sh.

New install: download the zip, unzip, move System Sentinel.app to Applications, then run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.

v0.8.20

New in 0.8.20

• Processes: sort by anything. Click a column title, or use the new Sort menu: name (A to Z), CPU, the 15 min / 1 hour / 6 hour average, memory or GPU.
• GPU column. Every process shows its share of the graphics chip.
• Calmer rows. The buttons on each row are now one ⋯ Actions menu (What is this?, Explain, Optimise, Kill, Force kill, sudo kill, More). The columns are wider and full process names fit. Badges are small icons; point at one to read it.
• "now" is now "CPU".
• GPU on Overview. A GPU chip sits next to the thermal chip on the main gauge.
• Clickable status chip. Click "memory pressure" (or disk, battery) at the top to open the tab about it.

Install / update

Already installed: click Install and relaunch when the update notice appears, or run ~/install-system-sentinel.sh.

New install: download the zip, unzip, move System Sentinel.app to Applications, then run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.

v0.8.19

New in 0.8.19

• Graphics (GPU) card on Overview. How busy the graphics chip is now and over the last hour, a chart of that hour, graphics memory in use, and which apps are using it right now.
• GPU on the Processes tab. Sort by GPU, and a "GPU 23%" pill on any process using the graphics chip.
• Checkup finds apps keeping the graphics chip busy. After 5 minutes of steady use by an app in the background (or flat out in front), it says what to do for that kind of app: find the tab in a browser, stop a local AI model, lower a game's settings. Buttons for Quit, Low Power Mode on battery, and Optimise screen when drawing the screen itself is the cost.

Install / update

• Already installed: click Install and relaunch when the update notice appears, or run ~/install-system-sentinel.sh.
• New install: download the zip, unzip, move System Sentinel.app to Applications, then run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.

v0.8.18

New in 0.8.18

• Nine tabs instead of eleven. Trends is now a page on Overview, and Rules a page on Settings.
• Checkup holds still while you read it. It refreshes when you run it again or come back after a minute, not mid-sentence.
• Stop an exposed service. When a database or server is open to the network, Checkup offers a Stop button for it.
• Plainer wording for unusual activity: "Mail is working 6 times harder than usual".
• Zero trust networks (Zscaler, Netskope, Cloudflare WARP). When pings are blocked, the internet is measured with TCP instead of showing as down, and the firewall is no longer flagged as off.
• Fewer, grouped notifications. Hotspot data use is one alert that updates in place and only makes a sound on joining and each GB. Alerts stack by kind (hotspot, alarms, heat, staying awake, reports, updates) and by app.

Install / update

• Already installed: click Install and relaunch when the update notice appears, or run ~/install-system-sentinel.sh.
• New install: download the zip, unzip, move System Sentinel.app to Applications, then run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.

v0.8.17

New in 0.8.17

• Remove a startup item: each item on the Rules tab under "Starts by itself" now has a bin button. It stops the item and moves its file to the Trash, so Put Back undoes it. Items installed for all users ask for your password.
• New Checkup symptom, "Display or dock": flags an external display stuck at 30 Hz (usually the cable), a display not at its full resolution, the one-external-display limit on a plain M1 or M2, a dock that crashed the Mac, and an overloaded screen-drawing process. It also lists what is plugged in.
• Docs: new screenshots including Checkup, and an up to date plan.

Install / update

Use Install and relaunch in the app, run ~/install-system-sentinel.sh (see the README), or download the zip below, move the app to Applications and run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.

v0.8.16

New in 0.8.16

• One place for what is wrong. The insights that used to sit at the bottom of the Overview are now on Checkup, under Found on its own, each with Ignore beside More. Findings that are not problems are under Worth knowing.
• Overview is the dashboard: load, Right now, Last hour, cores and memory. When Checkup has found something, a line at the top says how many and names the first; click it to go to Checkup.
• Said once: where a Checkup finding and an insight report the same thing (an app keeping the Mac awake, running hot, the disk filling, fast battery drain), it shows once, and ignoring either hides both.
• The Checkup badge and headline count everything that needs a look, leaving out what you have ignored.
• Card borders stand out in light and dark mode.

Install / update

Use Install and relaunch in the app, run ~/install-system-sentinel.sh (see the README), or download the zip below, move the app to Applications and run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.

v0.8.15

New in 0.8.15

• Checkup is the first tab, with "What's wrong?" at the top. System Sentinel diagnoses the Mac on its own (running hot, processor or memory short, battery draining fast, disk nearly full, an app keeping the Mac awake, a blocked app, a kernel panic) and lists each finding with Fix it. Or pick what feels wrong from ten symptoms: Slow or hot, Battery drains, Disk full, Wi-Fi or internet, Won't sleep, Mic or camera, App crashes or won't open, Bluetooth, iCloud stuck, Restarted by itself. Each opens one panel with what was found and the fixes.
• New checks behind the symptoms: apps refused the microphone or camera, with a one-click reset (needs Full Disk Access); apps macOS calls damaged, with "Allow it to open"; Bluetooth state and connected devices; the last kernel panic in a sentence, naming any non-Apple driver.
• Ignore a finding that is on purpose. A finding about a particular app stays ignored until Show again; a passing state (running hot, low disk) is hidden for a day.
• Crashes are not restarts. A burst of crashes that is over shows as history, not a warning, and command-line programs (compilers, scripts) are not told to reinstall.
• Performance first, security last in the Checkup sections. The Mac's own firewall being off is a note, not a warning: company firewalls and zero trust networks cover it.
• The app reopens on the tab you were last on, across relaunches.
• Route test runs for 1, 5 or 15 minutes or an hour, with a chart of delay and lost pings over time, a minute-by-minute table in the copied report, and a verdict on whether trouble was constant or came and went.
• An old version is obvious: the About button flashes orange and the version line says a newer one is out.

Install / update

Use Install and relaunch in the app, run ~/install-system-sentinel.sh (see the README), or download the zip below, move the app to Applications and run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.

v0.8.14

New in 0.8.14

• Route test (mtr) on the Network tab. Type a name or address (or tap 1.1.1.1, 8.8.8.8 or apple.com): it traces the route, then pings every hop once a second for a minute, showing loss, last, average, best, worst and jitter per hop and who runs each one. A verdict says whether loss carries on to the end and which hop it starts at (your network or your provider), flags delay jumps and jitter, and treats a router that only drops pings as normal. Copy report gives a plain-text table like mtr --report. Uses macOS's own traceroute and ping, so no admin password.
• "What is this?" opens in a floating window beside the main one, so it stays put while the process list re-sorts. Its numbers stay live.
• Quit apps stop being reported as growing. A memory insight no longer says an app (such as Rancher Desktop's virtual machine) is climbing after it has been quit.
• Battery wording: "Plugged in at 100% for 76% of the time".

Install / update

Run ~/install-system-sentinel.sh (see the README), or download the zip below, move the app to Applications and run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.

v0.8.13

New in 0.8.13

• Update results show where you asked. Check for updates in the About window reports in the About window, not in the menu window behind it.
• Messages stand out. Results now appear on a solid green (or red) banner with white text, so they are easy to see over the coloured cards.
• More colour, less grey. Footer buttons are colour coded (About indigo, Activity Monitor green, Quit red), Check for updates is solid blue in About and Settings, Reinstall is orange, and each About link has its own colour.

Install / update

Run ~/install-system-sentinel.sh (see the README), or download the zip below, move the app to Applications and run:

xattr -dr com.apple.quarantine "/Applications/System Sentinel.app"

The build isn't notarised by Apple; the source is public.