diff --git a/README.md b/README.md
index 849c041..ca58575 100644
--- a/README.md
+++ b/README.md
@@ -8,13 +8,13 @@ QEMU NVMe Testing Galore!
 running.
 
 
-## Getting Started (Manual Mode)
+## Getting Started
 
 1. Clone the `vmctl` repository.
 
 2. Bootstrap a config directory with the following command:
 
-       $ ./vmctl env --bootstrap $HOME/vms --verbose
+        $ ./vmctl env --bootstrap $HOME/vms --verbose
 
    **Note** This will:
     * Check that `ssh` and `socat` are installed
@@ -25,16 +25,17 @@ running.
 
 3. There are two ways of executing `vmctl`:
     1. Symlink in your path to always have it available "natively"
-
+        ```
         $ ln -s /path/to/vmctl/vmctl $HOME/bin/vmctl
         $ vmctl --help
         $ vmctl -c CONFIG <command>
-
+        ```
     2. Activate `vmctl` with `env` for your current shell
-
+        ```
         $ ./vmctl env --confdir $HOME/vms
         $ vmctl --help
         $ vmctl -c CONFIG <command>
+        ```
 
 4. Prepare a boot image. The base configruation `*-base.conf` will look for a
    base image in `img/base.qcow2`. You can use [archbase][archbase] to build a
diff --git a/cmd/run b/cmd/run
index 7d05554..97241fd 100644
--- a/cmd/run
+++ b/cmd/run
@@ -196,6 +196,15 @@ _run() {
   params=("${QEMU_PARAMS[@]}")
 
   if [[ -v do_print ]]; then
+    if [[ -v VMPRE ]]; then
+      echo "Before QEMU:"
+      for cmd in "${VMPRE[@]}"; do
+        echo -n "  $cmd"
+        echo
+      done
+    fi
+    echo
+
     local nargs="${#params[@]}"
 
     echo "$QEMU_SYSTEM_BINARY \\"
diff --git a/examples/vm/common.conf b/examples/vm/common.conf
index 90e257e..5d4058c 100644
--- a/examples/vm/common.conf
+++ b/examples/vm/common.conf
@@ -1,10 +1,10 @@
 #!/usr/bin/env bash
 
 # vmctl run parameters
-QEMU_IMG=$(/usr/bin/which qemu-img)
-QEMU_EDK2_AARCH64="/usr/share/edk2-armvirt/aarch64/QEMU_EFI.fd"
-GUEST_KERNEL_APPEND_EXTRA="audit=0"
-GUEST_KERNEL_BOOTDEV="/dev/vda1"
+: "${QEMU_IMG:=$(which qemu-img)}"
+: "${QEMU_EDK2_AARCH64:="/usr/share/edk2-armvirt/aarch64/QEMU_EFI.fd"}"
+: "${GUEST_KERNEL_APPEND_EXTRA:="audit=0"}"
+: "${GUEST_KERNEL_BOOTDEV:="/dev/vda1"}"
 
 # nvme-specific local parameters
-default_nvme_ns_extra="logical_block_size=4096,physical_block_size=4096"
+: "${default_nvme_ns_extra:="logical_block_size=4096,physical_block_size=4096"}"