Simple Sketchybar System Stats

This is a simple event provider for Sketchybar that sends system stats to Sketchybar via the event trigger system_stats.

Installation

Prebuilt binaries

You can download a prebuilt binary for Apple Silicon (aarch64) and Intel Macs (x86_64) from the latest release.

Build locally

1. Install the Rust toolchain.

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

2. Use cargo to build the binary:

git clone https://github.com/joncrangle/sketchybar-system-stats.git
cd sketchybar-system-stats
cargo build --release

CLI usage

Use the help command to get usage information:

$ stats_provider --help
A simple system stats event provider for Sketchybar.

Usage: stats_provider [OPTIONS]

Options:
  -a, --all                                        Get all stats
  -c, --cpu <CPU>...                               Get CPU stats [possible values: count, frequency, temperature, usage]
  -d, --disk <DISK>...                             Get disk stats [possible values: count, free, total, usage, used]
  -m, --memory <MEMORY>...                         Get memory stats [possible values: ram_available, ram_total, ram_usage, ram_used, swp_free, swp_total, swp_usage, swp_used]
  -n, --network <NETWORK>...                       Network rx/tx in KB/s. Specify network interfaces (e.g., -n eth0 en0 lo0). At least one is required.
  -s, --system <SYSTEM>...                         Get system stats [possible values: arch, distro, host_name, kernel_version, name, os_version, long_os_version]
  -u, --uptime <UPTIME>...                         Get uptime stats [possible values: week, day, hour, min, sec]
  -i, --interval <INTERVAL>                        Refresh interval in seconds [default: 5]
      --network-refresh-rate <NETWORK_REFRESH_RATE> Network refresh rate (how often to refresh network interface list, in stat intervals) [default: 5]
  -b, --bar <BAR>                                  Bar name (optional)
      --verbose                                    Enable verbose output
  -h, --help                                       Print help
  -V, --version                                    Print version

Example: trigger event with cpu, disk and ram usage percentages at a refresh interval of 2 seconds:

stats_provider --cpu usage --disk usage --memory ram_usage --interval 2

Example: network monitoring with optimized refresh rate:

# Monitor network with interface refresh every 8 stat intervals
stats_provider --network en0 --interval 3 --network-refresh-rate 8

Uptime Usage

The uptime system supports customizable time units. You can specify which units to display:

# Show all available units (week, day, hour, min, sec)
stats_provider --uptime

# Show specific units only
stats_provider --uptime day min    # Shows "5d 42m"
stats_provider --uptime week hour  # Shows "2w 5h"

Available uptime units:

• week (w) - weeks
• day (d) - days
• hour (h) - hours
• min (m) - minutes
• sec (s) - seconds

Units are automatically sorted from largest to smallest, with intelligent carry-over (e.g., excess hours carry into days).

Network Optimization

The --network-refresh-rate parameter controls how frequently the network interface list is refreshed:

# Default: refresh network interfaces every 5 stat intervals
stats_provider --network en0 --interval 2 --network-refresh-rate 5

# More frequent refresh (every 2 intervals) for dynamic environments
stats_provider --network en0 wlan0 --network-refresh-rate 2

# Less frequent refresh (every 10 intervals) for stable setups to reduce overhead
stats_provider --network en0 --network-refresh-rate 10

Benefits:

• Performance: Reduces system calls by refreshing interface list less frequently
• Efficiency: Network interfaces don't change rapidly, so frequent rescanning is unnecessary
• Customizable: Adjust based on your network environment stability

Recommendation: Use higher values (8-15) for stable network setups, lower values (2-5) for environments where interfaces frequently change.

Add the --verbose flag to see more detailed output:

$ stats_provider --cpu usage --disk usage --memory ram_usage --interval 2 --verbose
SketchyBar Stats Provider is running.
Stats Provider CLI: Cli { all: false, cpu: Some(["usage"]), disk: Some(["usage"]), memory: Some(["ram_usage"]), network: None, system: None, interval: 2, bar: None, verbose: true }
Successfully sent to SketchyBar: --add event system_stats
Current message: CPU_USAGE="4%" DISK_USAGE="65%" RAM_USAGE="54%"
Successfully sent to SketchyBar: --trigger system_stats CPU_USAGE="4%" DISK_USAGE="65%" RAM_USAGE="54%"
Current message: CPU_USAGE="6%" DISK_USAGE="65%" RAM_USAGE="54%"
Successfully sent to SketchyBar: --trigger system_stats CPU_USAGE="6%" DISK_USAGE="65%" RAM_USAGE="54%"
Current message: CPU_USAGE="5%" DISK_USAGE="65%" RAM_USAGE="54%"
Successfully sent to SketchyBar: --trigger system_stats CPU_USAGE="5%" DISK_USAGE="65%" RAM_USAGE="54%"

Usage with Sketchybar

Environment variables that can be provided by the system_stats event

Variable	Description
ARCH	System architecture
CPU_COUNT	Number of CPU cores
CPU_FREQUENCY	CPU frequency MHz
CPU_TEMP	CPU temperature °C
CPU_USAGE	CPU usage %
DISK_COUNT	Number of disks
DISK_FREE	Free disk space GB
DISK_TOTAL	Total disk space GB
DISK_USAGE	Disk usage %
DISK_USED	Used disk space GB
DISTRO	System distribution
HOST_NAME	System host name
KERNEL_VERSION	System kernel version
NETWORK_RX_{INTERFACE}	Received KB/s from specified interface
NETWORK_TX_{INTERFACE}	Transmitted KB/s from specified interface
OS_VERSION	System OS version
LONG_OS_VERSION	System long OS version
RAM_TOTAL	Total memory GB
RAM_AVAILABLE	Available memory GB
RAM_TOTAL	Total memory GB
RAM_USAGE	Memory usage %
RAM_USED	Used memory GB
SWP_FREE	Free swap GB
SWP_TOTAL	Total swap GB
SWP_USAGE	Swap usage %
SWP_USED	Used swap GB
SYSTEM_NAME	System name (i.e. Darwin)
UPTIME	System uptime (customizable units)

Note

System stats that are not expected to change between system restarts (e.g. NAME, OS_VERSION, etc.) are sent when the app binary starts, but are not refreshed.

sketchybarrc file

Run stats_provider with desired options by including it in your sketchybarrc config:

killall stats_provider
# Update with path to stats_provider
$CONFIG_DIR/sketchybar-system-stats/target/release/stats_provider --cpu usage --disk usage --memory ram_usage &

Example: use stats_provider to add an item disk_usage, subscribe to the system_stats event and update the disk_usage item.

# Ensure that `stats_provider` is running by invoking it earlier in your `sketchybarrc` file
sketchybar --add item disk_usage right \
           --set disk_usage script="sketchybar --set disk_usage label=\$DISK_USAGE" \
           --subscribe disk_usage system_stats

SbarLua module

-- Update with path to stats_provider
sbar.exec('killall stats_provider >/dev/null; $CONFIG_DIR/sketchybar-system-stats/target/release/stats_provider --cpu usage --disk usage --memory ram_usage')

-- Subscribe and use the `DISK_USAGE` var
local disk = sbar.add('item', 'disk', {
	position = 'right',
})
disk:subscribe('system_stats', function(env)
	disk:set { label = env.DISK_USAGE }
end)

Why?

I wanted a single simple, lightweight binary to provide stats to Sketchybar. I also wanted to learn how to code in Rust, and learning by doing is a great way to learn.

Thanks

• Sketchybar and SbarLua
• sketchybar-rs