diff --git a/bin/macos_battery_exporter b/bin/macos_battery_exporter
new file mode 100755
index 0000000..6e8610d
--- /dev/null
+++ b/bin/macos_battery_exporter
@@ -0,0 +1,81 @@
+#! /usr/bin/env ruby
+# frozen_string_literal: true
+
+require 'json'
+
+class MacOSBatteryExporter
+  def export
+    puts metrics
+  end
+
+  def metrics
+    <<~METRICS
+      # HELP node_battery_charge_percent Battery charge percent
+      # TYPE node_battery_charge_percent gauge
+      node_battery_charge_percent{serial="#{battery_serial_number}"} #{charge_percentage}
+      # HELP node_battery_charge_ampere Battery charge ampere
+      # TYPE node_battery_charge_ampere gauge
+      node_battery_charge_ampere{serial="#{battery_serial_number}"} #{charge_info['sppower_battery_current_capacity'] / 1000.0}
+      # HELP node_battery_full_charge_ampere Battery full charge capacity
+      # TYPE node_battery_full_charge_ampere gauge
+      node_battery_full_charge_ampere{serial="#{battery_serial_number}"} #{charge_info['sppower_battery_max_capacity'] / 1000.0}
+      # HELP node_battery_current_flow_ampere Current flow of ampere in (+) or out (-) of battery
+      # TYPE node_battery_current_flow_ampere gauge
+      node_battery_current_flow_ampere{serial="#{battery_serial_number}"} #{battery_info['sppower_current_amperage'] / 1000.0}
+      # HELP node_battery_charger_connected Is charger connected?
+      # TYPE node_battery_charger_connected gauge
+      node_battery_charger_connected{serial="#{battery_serial_number}"} #{ac_charger_info['sppower_battery_charger_connected'] == 'TRUE' ? 1.0 : 0.0}
+      # HELP node_battery_is_charging Is charger connected?
+      # TYPE node_battery_is_charging gauge
+      node_battery_is_charging{serial="#{battery_serial_number}"} #{ac_charger_info['sppower_battery_is_charging'] == 'TRUE' ? 1.0 : 0.0}
+      # HELP node_battery_charger_watts Watts provided by charger
+      # TYPE node_battery_charger_watts gauge
+      node_battery_charger_watts{serial="#{battery_serial_number}"} #{ac_charger_info['sppower_ac_charger_watts'].to_f}
+      # HELP node_battery_fully_charged Is battery fully charged?
+      # TYPE node_battery_fully_charged gauge
+      node_battery_fully_charged{serial="#{battery_serial_number}"} #{ac_charger_info['sppower_battery_fully_charged'] == 'TRUE' ? 1.0 : 0.0}
+      # HELP node_battery_cycle_count Battery cycle count
+      # TYPE node_battery_cycle_count counter
+      node_battery_cycle_count{serial="#{battery_serial_number}"} #{health_info['sppower_battery_cycle_count']}
+    METRICS
+  end
+
+  def charge_percentage
+    @charge_percentage ||=
+      `pmset -g batt | grep -Eo '\\d+%' | cut -d% -f1`.strip
+  end
+
+  def battery_serial_number
+    battery_info.dig(
+      'sppower_battery_model_info',
+      'sppower_battery_serial_number'
+    )
+  end
+
+  def charge_info
+    @charge_info ||= battery_info['sppower_battery_charge_info']
+  end
+
+  def health_info
+    @health_info ||= battery_info['sppower_battery_health_info']
+  end
+
+  def battery_info
+    @battery_info ||= power_data&.find do |v|
+      v['_name'] == 'spbattery_information'
+    end
+  end
+
+  def ac_charger_info
+    @ac_charger_info ||= power_data&.find do |v|
+      v['_name'] == 'sppower_ac_charger_information'
+    end
+  end
+
+  def power_data
+    @power_data ||= JSON.parse(`system_profiler SPPowerDataType -json`)
+                        &.[]('SPPowerDataType')
+  end
+end
+
+MacOSBatteryExporter.new.export if __FILE__ == $PROGRAM_NAME
diff --git a/launch_agents/me.jimeh.macos-battery-exporter.plist b/launch_agents/me.jimeh.macos-battery-exporter.plist
new file mode 100644
index 0000000..5cc66d4
--- /dev/null
+++ b/launch_agents/me.jimeh.macos-battery-exporter.plist
@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+  <dict>
+    <key>Disabled</key>
+    <false/>
+    <key>Label</key>
+    <string>me.jimeh.macos-battery-exporter</string>
+    <key>ProgramArguments</key>
+    <array>
+      <string>sh</string>
+      <string>-c</string>
+      <string>$HOME/.dotfiles/bin/macos_battery_exporter > $HOME/.node_metrics/battery.prom</string>
+    </array>
+    <key>RunAtLoad</key>
+    <false/>
+    <key>EnvironmentVariables</key>
+    <dict>
+      <key>PATH</key>
+      <string>/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/local/sbin</string>
+    </dict>
+    <key>StartInterval</key>
+    <integer>30</integer>
+  </dict>
+</plist>
diff --git a/zsh/ruby.zsh b/zsh/ruby.zsh
index ce225e2..d02df35 100755
--- a/zsh/ruby.zsh
+++ b/zsh/ruby.zsh
@@ -39,19 +39,15 @@ alias cu="bundle exec cucumber"
 alias scu="RAILS_ENV=cucumber bundle exec spring cucumber"
 alias va="vagrant"
 
-alias bc="bundle check"
+# Bundler aliases
+alias bcn="bundle clean"
 alias bco="bundle console"
-
-if [ -n "$BASH_VERSION" ]; then
-  # Bundler aliases
-  alias be="bundle exec"
-  alias bl="bundle list"
-  alias bp="bundle package"
-  alias bo="bundle open"
-  alias bu="bundle update"
-  alias bi="bundle_install"
-  alias bcn="bundle clean"
-fi
+alias be="bundle exec"
+alias bi="bundle_install"
+alias bl="bundle list"
+alias bo="bundle open"
+alias bp="bundle package"
+alias bu="bundle update"
 
 # lazy-load rbenv
 if [ -d "$HOME/.rbenv/shims" ]; then