diff --git a/left/build/kds/blhost-unix.sh b/left/build/kds/blhost-unix.sh
deleted file mode 100755
index 586fdf1..0000000
--- a/left/build/kds/blhost-unix.sh
+++ /dev/null
@@ -1,56 +0,0 @@
-#!/bin/bash
-set -e # fail the script if a command fails
-
-if [ -z "$1" ]; then
-    echo "No firmware image specified"
-    exit 1
-fi
-
-firmware_image="`pwd`/$1"
-
-if [ ${firmware_image: -4} != ".bin" ]; then
-    echo "Firmware image extension is not .bin"
-    exit 1
-fi
-
-if [ ! -f "$firmware_image" ]; then
-    echo "Firmware image does not exist"
-    exit 1
-fi
-
-PATH=$PATH:/usr/local/bin # This should make node and npm accessible on OSX.
-usb_dir=../../../lib/agent/packages/usb
-usb_binding=$usb_dir/node_modules/usb/build/Release/usb_bindings.node
-
-case "$(uname -s)" in
-   Linux)
-     blhost_path=linux/amd64
-     ;;
-   Darwin)
-     blhost_path=mac
-     ;;
-   *)
-     echo "Your operating system is not supported."
-     exit 1
-     ;;
-esac
-
-blhost_usb="../../../lib/bootloader/bin/Tools/blhost/$blhost_path/blhost --usb 0x1d50,0x6121"
-blhost_buspal="$blhost_usb --buspal i2c,0x10,100k"
-
-set -x # echo on
-
-#if [ ! -f $usb_binding ]; then
-#   cd $usb_dir
-#   npm install
-#fi
-
-$usb_dir/send-kboot-command-to-slave.js ping 0x10
-$usb_dir/jump-to-slave-bootloader.js
-$usb_dir/reenumerate.js buspal
-$blhost_buspal get-property 1
-$blhost_buspal flash-erase-all-unsecure
-$blhost_buspal write-memory 0x0 "$firmware_image"
-$blhost_usb reset
-$usb_dir/reenumerate.js normalKeyboard
-$usb_dir/send-kboot-command-to-slave.js reset 0x10
diff --git a/package.json b/package.json
index 00ad51b..3a39c42 100644
--- a/package.json
+++ b/package.json
@@ -11,6 +11,10 @@
   "bugs": {
     "url": "https://github.com/UltimateHackingKeyboard/firmware/issues"
   },
+  "dependencies": {
+    "commander": "^2.11.0",
+    "shelljs": "^0.7.8"
+  },
   "version": "2.1.0",
   "dataModelVersion": "1.0.0",
   "usbProtocolVersion": "1.2.0",
diff --git a/scripts/update-slave-firmware.js b/scripts/update-slave-firmware.js
new file mode 100755
index 0000000..9548e87
--- /dev/null
+++ b/scripts/update-slave-firmware.js
@@ -0,0 +1,61 @@
+#!/usr/bin/env node
+const program = require('commander');
+require('shelljs/global');
+
+config.fatal = true;
+
+program
+    .usage('update-slave-firmware <firmware-image>')
+    .parse(process.argv)
+
+const firmwareImage = program.args[0];
+
+if (!firmwareImage) {
+    echo('No firmware image specified');
+    exit(1);
+}
+
+if (!firmwareImage.endsWith('.bin')) {
+    echo('Firmware image extension is not .bin');
+    exit(1);
+}
+
+if (!test('-f', firmwareImage)) {
+    echo('Firmware image does not exist');
+    exit(1);
+}
+
+var usbDir = '../../../lib/agent/packages/usb';
+var usbBinding = usbDir + '/node_modules/usb/build/Release/usb_bindings.node';
+
+let blhostPath;
+switch (process.platform) {
+    case 'linux':
+        blhostPath = 'linux/amd64/blhost';
+        break;
+    case 'darwin':
+        blhostPath = 'mac/blhost';
+        break;
+    case 'win32':
+        blhostPath = 'win/blhost.exe';
+        break;
+    default:
+        echo('Your operating system is not supported');
+        exit(1);
+        break;
+}
+
+var blhostUsb = `../../../lib/bootloader/bin/Tools/blhost/${blhostPath} --usb 0x1d50,0x6121`;
+var blhostBuspal = blhostUsb + ' --buspal i2c,0x10,100k';
+
+config.verbose = true;
+
+exec(`${usbDir}/send-kboot-command-to-slave.js ping 0x10`);
+exec(`${usbDir}/jump-to-slave-bootloader.js`);
+exec(`${usbDir}/reenumerate.js buspal`);
+exec(`${blhostBuspal} get-property 1`);
+exec(`${blhostBuspal} flash-erase-all-unsecure`);
+exec(`${blhostBuspal} write-memory 0x0 ${firmwareImage}`);
+exec(`${blhostUsb} reset`);
+exec(`${usbDir}/reenumerate.js normalKeyboard`);
+exec(`${usbDir}/send-kboot-command-to-slave.js reset 0x10`);