diff --git a/qemu/launchers/kvm b/qemu/launchers/kvm
index 26df626..ff41c26 100755
--- a/qemu/launchers/kvm
+++ b/qemu/launchers/kvm
@@ -1,34 +1,21 @@
-#!/usr/bin/env python3
+#!/usr/bin/env sh
+set -x
 
-# Set number of vCPUs to use to the environment variable QEMUSH_NPROC or
-# half of total vCPUs installed if it fails
-try:
-    from os import environ
-    nproc = environ['QEMUSH_NPROC']
-except KeyError:
-    from multiprocessing import cpu_count
-    nproc = str(cpu_count() // 2)
+# How many CPU cores to use
+nproc=$QEMUSH_NPROC
+[ -z "$nproc" ] && nproc=$(($(nproc) / 2))
 
-# Set amount of RAM to use to the environment variable QEMUSH_RAM or half
-# of total RAM installed if it fails
-try:
-    ram = environ['QEMUSH_RAM']
-except KeyError:
-    from psutil import virtual_memory
-    ram = str(virtual_memory().available // 2 // (1024 ** 2))
+# How much RAM to use
+ram=$QEMUSH_RAM
+[ -z "$ram" ] && ram=$(($(free | grep '^Mem:\s' | awk '{ print $NF }') / 2))K
 
-# Set the command to initialize; all required parameters to make a sane KVM
-# are included and optional arguments are appended from argv
-from sys import argv
-command = [
-    'qemu-system-x86_64',
-    '-enable-kvm',
-    '-M', 'q35',
-    '-cpu', 'host', '-smp', nproc,
-    '-m', ram,
-] + argv[1:]
+# Set the arguments
+set -- qemu-system-x86_64 \
+    -enable-kvm \
+    -M q35 \
+    -cpu host -smp "$nproc" \
+    -m "$ram" \
+    "$@"
 
-# Print the final command and replace the main process with it
-print(command)
-from os import execvp
-execvp(command[0], command)
+# Start the machine
+exec "$@"