diff --git a/configure b/configure
index 142d72b..b7a3d07 100755
--- a/configure
+++ b/configure
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 # We don't support srcdir != builddir
 echo \#buildapi-variable-no-builddir > /dev/null
@@ -23,9 +23,9 @@ CC="${CC:-cc}"
 PKG_CONFIG="${PKG_CONFIG:-pkg-config}"
 
 # set configprofile based on ID and ID_LIKE from os-release
-if [[ -f /etc/os-release ]]; then
+if [ -f /etc/os-release ]; then
     . /etc/os-release
-elif [[ -f /usr/lib/os-release ]]; then
+elif [ -f /usr/lib/os-release ]; then
     . /usr/lib/os-release
 fi
 
@@ -51,19 +51,20 @@ read_arg() {
     # $1 = arg name
     # $2 = arg value
     # $3 = arg parameter
-    local rematch='^[^=]*=(.*)$'
-    if [[ $2 =~ $rematch ]]; then
-        read -r "$1" <<< "${BASH_REMATCH[1]}"
+    if [ "${2#*=}" != "$2" ]; then
+        value=${2#*=}
     else
-        read -r "$1" <<< "$3"
+        value=$3
         # There is no way to shift our callers args, so
         # return 1 to indicate they should do it instead.
+        eval "$1=\$value"
         return 1
     fi
+    eval "$1=\$value"
     return 0
 }
 
-while (($# > 0)); do
+while [ "$#" -gt 0 ]; do
     case "${1%%=*}" in
         --prefix) read_arg prefix "$@" || shift ;;
         --libdir) read_arg libdir "$@" || shift ;;
@@ -98,7 +99,7 @@ if ! ${PKG_CONFIG} --exists --print-errors " libkmod >= 23 "; then
     exit 1
 fi
 
-if ! ${CC} -c -o /dev/null /dev/null &> /dev/null; then
+if ! ${CC} -c -o /dev/null /dev/null > /dev/null 2>&1; then
     echo "dracut needs a C compiler (${CC} not found)." >&2
     exit 1
 fi
@@ -200,7 +201,7 @@ ret=$?
 rm -f weakdep_test.c a.out
 
 if test $ret -eq 0; then
-    KMOD_CFLAGS_EXTRA+=" -DCONFIG_WEAKDEP"
+    KMOD_CFLAGS_EXTRA="${KMOD_CFLAGS_EXTRA-} -DCONFIG_WEAKDEP"
 fi
 
 cat > Makefile.inc.$$ << EOF
@@ -225,16 +226,16 @@ SYSTEMD_LIBS ?= $(${PKG_CONFIG} --silence-errors --libs "libsystemd >= 257")
 EOF
 
 {
-    [[ $programprefix ]] && echo "programprefix ?= ${programprefix}"
-    [[ $execprefix ]] && echo "execprefix ?= ${execprefix}"
-    [[ $includedir ]] && echo "includedir ?= ${includedir}"
-    [[ $libexecdir ]] && echo "libexecdir ?= ${libexecdir}"
-    [[ $localstatedir ]] && echo "localstatedir ?= ${localstatedir}"
-    [[ $sharedstatedir ]] && echo "sharedstatedir ?= ${sharedstatedir}"
-    [[ $infodir ]] && echo "infodir ?= ${infodir}"
-    [[ $systemdsystemunitdir ]] && echo "systemdsystemunitdir ?= ${systemdsystemunitdir}"
-    [[ $bashcompletiondir ]] && echo "bashcompletiondir ?= ${bashcompletiondir}"
-    [[ $configprofile ]] && echo "configprofile ?= ${configprofile}"
+    [ -n "$programprefix" ] && echo "programprefix ?= ${programprefix}"
+    [ -n "$execprefix" ] && echo "execprefix ?= ${execprefix}"
+    [ -n "$includedir" ] && echo "includedir ?= ${includedir}"
+    [ -n "$libexecdir" ] && echo "libexecdir ?= ${libexecdir}"
+    [ -n "$localstatedir" ] && echo "localstatedir ?= ${localstatedir}"
+    [ -n "$sharedstatedir" ] && echo "sharedstatedir ?= ${sharedstatedir}"
+    [ -n "$infodir" ] && echo "infodir ?= ${infodir}"
+    [ -n "$systemdsystemunitdir" ] && echo "systemdsystemunitdir ?= ${systemdsystemunitdir}"
+    [ -n "$bashcompletiondir" ] && echo "bashcompletiondir ?= ${bashcompletiondir}"
+    [ -n "$configprofile" ] && echo "configprofile ?= ${configprofile}"
 } >> Makefile.inc.$$
 
 mv Makefile.inc.$$ Makefile.inc
diff --git a/dracut-catimages.sh b/dracut-catimages.sh
index 608fb49..754894c 100755
--- a/dracut-catimages.sh
+++ b/dracut-catimages.sh
@@ -1,4 +1,4 @@
-#!/bin/bash --norc
+#!/bin/sh
 #
 # Copyright 2009 Red Hat, Inc.  All rights reserved.
 #
@@ -17,7 +17,7 @@
 #
 
 dinfo() {
-    [[ $beverbose ]] && echo "$@" >&2
+    [ -n "$beverbose" ] && echo "$@" >&2
 }
 
 derror() {
@@ -47,7 +47,7 @@ EOF
 imagedir=/var/lib/dracut/images
 overlay=/var/lib/dracut/overlay
 
-while (($# > 0)); do
+while [ "$#" -gt 0 ]; do
     case $1 in
         -f | --force) force=yes ;;
         -i | --imagedir)
@@ -83,7 +83,7 @@ done
 outfile=$1
 shift
 
-if [[ -z $outfile ]]; then
+if [ -z "$outfile" ]; then
     derror "No output file specified."
     usage
     exit 1
@@ -92,32 +92,32 @@ fi
 baseimage=$1
 shift
 
-if [[ -z $baseimage ]]; then
+if [ -z "$baseimage" ]; then
     derror "No base image specified."
     usage
     exit 1
 fi
 
-if [[ -f $outfile && ! $force ]]; then
+if [ -f "$outfile" ] && [ -z "$force" ]; then
     derror "Will not override existing initramfs ($outfile) without --force"
     exit 1
 fi
 
-if [[ ! $no_imagedir && ! -d $imagedir ]]; then
+if [ -z "$no_imagedir" ] && [ ! -d "$imagedir" ]; then
     derror "Image directory $imagedir is not a directory"
     exit 1
 fi
 
-if [[ ! $no_overlay && ! -d $overlay ]]; then
+if [ -z "$no_overlay" ] && [ ! -d "$overlay" ]; then
     derror "Overlay $overlay is not a directory"
     exit 1
 fi
 
-if [[ ! $no_overlay ]]; then
-    if [[ ! $no_imagedir ]]; then
+if [ -z "$no_overlay" ]; then
+    if [ -z "$no_imagedir" ]; then
         ofile="$imagedir/90-overlay.img"
         dinfo "Creating image $ofile from directory $overlay"
-        type pigz &> /dev/null && gzip=pigz || gzip=gzip
+        command -v pigz > /dev/null 2>&1 && gzip=pigz || gzip=gzip
         (
             cd "$overlay" || return 1
             find . | cpio --quiet -H newc -o | $gzip -9 > "$ofile"
@@ -127,18 +127,18 @@ if [[ ! $no_overlay ]]; then
     fi
 fi
 
-if [[ ! $no_imagedir ]]; then
+dinfo "Using base image $baseimage"
+cat -- "$baseimage" > "$outfile"
+
+if [ -z "$no_imagedir" ]; then
     for i in "$imagedir/"*.img; do
-        [[ -f $i ]] && images+=("$i")
+        [ -f "$i" ] || continue
+        dinfo "Appending $i"
+        cat -- "$i" >> "$outfile"
     done
 fi
 
-images+=("$@")
-
-dinfo "Using base image $baseimage"
-cat -- "$baseimage" > "$outfile"
-
-for i in "${images[@]}"; do
+for i in "$@"; do
     dinfo "Appending $i"
     cat -- "$i" >> "$outfile"
 done
diff --git a/dracut-initramfs-restore.sh b/dracut-initramfs-restore.sh
index 828edca..1e82422 100755
--- a/dracut-initramfs-restore.sh
+++ b/dracut-initramfs-restore.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 set -e
 
@@ -13,19 +13,18 @@ trap 'echo "Received SIGTERM signal, ignoring!" >&2' TERM
 
 KERNEL_VERSION="$(uname -r)"
 
-[[ $dracutbasedir ]] || dracutbasedir=/usr/lib/dracut
+[ -n "$dracutbasedir" ] || dracutbasedir=/usr/lib/dracut
 SKIP="$dracutbasedir/skipcpio"
-[[ -x $SKIP ]] || SKIP="cat"
+[ -x "$SKIP" ] || SKIP="cat"
 
 find_initrd_for_kernel_version() {
-    local kernel_version="$1"
-    local base_path files initrd machine_id
+    kernel_version=$1
 
-    if [[ -d /efi/Default ]] || [[ -d /boot/Default ]] || [[ -d /boot/efi/Default ]]; then
+    if [ -d /efi/Default ] || [ -d /boot/Default ] || [ -d /boot/efi/Default ]; then
         machine_id="Default"
-    elif [[ -s /etc/machine-id ]]; then
+    elif [ -s /etc/machine-id ]; then
         read -r machine_id < /etc/machine-id
-        [[ $machine_id == "uninitialized" ]] && machine_id="Default"
+        [ "$machine_id" = "uninitialized" ] && machine_id="Default"
     else
         machine_id="Default"
     fi
@@ -40,27 +39,26 @@ find_initrd_for_kernel_version() {
         done
     fi
 
-    if [[ -f /lib/modules/${kernel_version}/initrd ]]; then
+    if [ -f "/lib/modules/${kernel_version}/initrd" ]; then
         echo "/lib/modules/${kernel_version}/initrd"
-    elif [[ -f /boot/initramfs-${kernel_version}.img ]]; then
+    elif [ -f "/boot/initramfs-${kernel_version}.img" ]; then
         echo "/boot/initramfs-${kernel_version}.img"
     else
-        files=(/boot/initr*"${kernel_version}"*)
-        if [ "${#files[@]}" -ge 1 ] && [ -e "${files[0]}" ]; then
-            echo "${files[0]}"
-        fi
+        for initrd in /boot/initr*"${kernel_version}"*; do
+            [ -e "$initrd" ] && echo "$initrd" && return
+        done
     fi
 }
 
-mount -o ro /boot &> /dev/null || true
+mount -o ro /boot > /dev/null 2>&1 || true
 
 IMG=$(find_initrd_for_kernel_version "$KERNEL_VERSION")
 if [ -z "$IMG" ]; then
-    if [[ -f /boot/initramfs-linux.img ]]; then
+    if [ -f /boot/initramfs-linux.img ]; then
         IMG="/boot/initramfs-linux.img"
-    elif [[ -f /boot/initrd.img ]]; then
+    elif [ -f /boot/initrd.img ]; then
         IMG="/boot/initrd.img"
-    elif [[ -f /initrd.img ]]; then
+    elif [ -f /initrd.img ]; then
         IMG="/initrd.img"
     else
         echo "No initramfs image found to restore!"
@@ -85,13 +83,13 @@ else
     exit 1
 fi
 
-if [[ -f squashfs-root.img ]]; then
+if [ -f squashfs-root.img ]; then
     if ! unsquashfs -no-xattrs -f -d . squashfs-root.img > /dev/null; then
         echo "Squash module is enabled for this initramfs but failed to unpack squash-root.img" >&2
         rm -f -- /run/initramfs/shutdown
         exit 1
     fi
-elif [[ -f erofs-root.img ]]; then
+elif [ -f erofs-root.img ]; then
     if ! fsck.erofs --extract=. --overwrite erofs-root.img > /dev/null; then
         echo "Squash module is enabled for this initramfs but failed to unpack erofs-root.img" >&2
         rm -f -- /run/initramfs/shutdown
@@ -102,7 +100,7 @@ fi
 if grep -qs -w selinux /sys/kernel/security/lsm \
     && [ -e /etc/selinux/config ] && [ -x /usr/sbin/setfiles ]; then
     . /etc/selinux/config
-    if [[ $SELINUX != "disabled" && -n $SELINUXTYPE ]]; then
+    if [ "$SELINUX" != "disabled" ] && [ -n "$SELINUXTYPE" ]; then
         /usr/sbin/setfiles -v -r /run/initramfs /etc/selinux/"${SELINUXTYPE}"/contexts/files/file_contexts /run/initramfs > /dev/null
     fi
 fi
diff --git a/install.d/50-dracut.install b/install.d/50-dracut.install
index 14f8772..6865ac8 100755
--- a/install.d/50-dracut.install
+++ b/install.d/50-dracut.install
@@ -1,4 +1,6 @@
-#!/bin/bash
+#!/bin/sh
+
+set -f
 
 COMMAND="${1:?}"
 KERNEL_VERSION="${2:?}"
@@ -7,16 +9,16 @@ BOOT_DIR_ABS="$3"
 KERNEL_IMAGE="$4"
 
 # If the initrd was provided on the kernel command line, we shouldn't generate our own.
-if [[ "$COMMAND" != "add" || "$#" -gt 4 ]]; then
+if [ "$COMMAND" != "add" ] || [ "$#" -gt 4 ]; then
     exit 0
 fi
 
 # Do not attempt to create initramfs if the supplied image is already a UKI
-if [[ "$KERNEL_INSTALL_IMAGE_TYPE" = "uki" ]]; then
+if [ "$KERNEL_INSTALL_IMAGE_TYPE" = "uki" ]; then
     exit 0
 fi
 
-if [[ "${KERNEL_INSTALL_INITRD_GENERATOR:-dracut}" = "dracut" ]]; then
+if [ "${KERNEL_INSTALL_INITRD_GENERATOR:-dracut}" = "dracut" ]; then
     # We are the initrd generator
     IMAGE="initrd"
     UEFI_OPTS="--no-uefi"
@@ -24,16 +26,16 @@ else
     exit 0
 fi
 
-if [[ "$KERNEL_INSTALL_UKI_GENERATOR" = "dracut" ]]; then
+if [ "$KERNEL_INSTALL_UKI_GENERATOR" = "dracut" ]; then
     # We are chosen to generate the UKI as well as initrd
     IMAGE="uki.efi"
     UEFI_OPTS="--uefi"
 fi
 
-if [[ -f ${KERNEL_IMAGE%/*}/$IMAGE ]]; then
+if [ -f "${KERNEL_IMAGE%/*}/$IMAGE" ]; then
     # we found an initrd or uki.efi at the same place as the kernel
     # use this and don't generate a new one
-    [[ $KERNEL_INSTALL_VERBOSE == 1 ]] && echo \
+    [ "$KERNEL_INSTALL_VERBOSE" = 1 ] && echo \
         "There is an $IMAGE image at the same place as the kernel, skipping generating a new one"
     cp --reflink=auto "${KERNEL_IMAGE%/*}/$IMAGE" "$KERNEL_INSTALL_STAGING_AREA/$IMAGE" \
         && chown root:root "$KERNEL_INSTALL_STAGING_AREA/$IMAGE" \
@@ -42,38 +44,39 @@ if [[ -f ${KERNEL_IMAGE%/*}/$IMAGE ]]; then
 fi
 
 if [ -n "$KERNEL_INSTALL_CONF_ROOT" ]; then
-    if [ -f "$KERNEL_INSTALL_CONF_ROOT/cmdline" ]; then
-        read -r -d '' -a BOOT_OPTIONS < "$KERNEL_INSTALL_CONF_ROOT/cmdline"
-    fi
-elif [[ -f /etc/kernel/cmdline ]]; then
-    read -r -d '' -a BOOT_OPTIONS < /etc/kernel/cmdline
-elif [[ -f /usr/lib/kernel/cmdline ]]; then
-    read -r -d '' -a BOOT_OPTIONS < /usr/lib/kernel/cmdline
+    cmdline="$KERNEL_INSTALL_CONF_ROOT/cmdline"
+elif [ -f /etc/kernel/cmdline ]; then
+    cmdline=/etc/kernel/cmdline
+elif [ -f /usr/lib/kernel/cmdline ]; then
+    cmdline=/usr/lib/kernel/cmdline
 else
-    declare -a BOOT_OPTIONS
+    cmdline=/proc/cmdline
+fi
 
-    read -r -d '' -a line < /proc/cmdline
-    for i in "${line[@]}"; do
-        [[ ${i#initrd=*} != "$i" ]] && continue
-        BOOT_OPTIONS+=("$i")
+BOOT_OPTIONS=
+if [ -f "$cmdline" ]; then
+    for i in $(cat "$cmdline"); do
+        case $i in
+            initrd=*) ;;
+            *) BOOT_OPTIONS="${BOOT_OPTIONS}${BOOT_OPTIONS:+ }$i" ;;
+        esac
     done
 fi
 
 unset noimageifnotneeded
 
-for ((i = 0; i < "${#BOOT_OPTIONS[@]}"; i++)); do
-    # shellcheck disable=SC1001
-    if [[ ${BOOT_OPTIONS[$i]} == root\=PARTUUID\=* ]]; then
+for i in $BOOT_OPTIONS; do
+    case $i in
+        root=PARTUUID=*)
         noimageifnotneeded="yes"
         break
-    fi
+        ;;
+    esac
 done
 
-# shellcheck disable=SC2046
-dracut -f \
-    ${noimageifnotneeded:+--noimageifnotneeded} \
-    $([[ $KERNEL_INSTALL_VERBOSE == 1 ]] && echo --verbose) \
-    $([[ -n $KERNEL_IMAGE ]] && echo --kernel-image "$KERNEL_IMAGE") \
-    "$UEFI_OPTS" \
-    --kver "$KERNEL_VERSION" \
-    "$KERNEL_INSTALL_STAGING_AREA/$IMAGE" || exit 1
+set -- dracut -f
+[ -n "$noimageifnotneeded" ] && set -- "$@" --noimageifnotneeded
+[ "$KERNEL_INSTALL_VERBOSE" = 1 ] && set -- "$@" --verbose
+[ -n "$KERNEL_IMAGE" ] && set -- "$@" --kernel-image "$KERNEL_IMAGE"
+set -- "$@" "$UEFI_OPTS" --kver "$KERNEL_VERSION" "$KERNEL_INSTALL_STAGING_AREA/$IMAGE"
+"$@" || exit 1
diff --git a/install.d/51-dracut-rescue.install b/install.d/51-dracut-rescue.install
index f49d7a7..701e5e8 100755
--- a/install.d/51-dracut-rescue.install
+++ b/install.d/51-dracut-rescue.install
@@ -1,6 +1,7 @@
-#!/bin/bash
+#!/bin/sh
 
 export LANG=C
+set -f
 
 COMMAND="${1:?}"
 KERNEL_VERSION="${2:?}"
@@ -8,19 +9,19 @@ BOOT_DIR_ABS="${3%/*}/0-rescue"
 KERNEL_IMAGE="$4"
 
 # If the initrd was provided on the kernel command line, we shouldn't generate our own.
-if [[ "$COMMAND" = "add" && "$#" -gt 4 ]]; then
+if [ "$COMMAND" = "add" ] && [ "$#" -gt 4 ]; then
     exit 0
 fi
 
 # Do not attempt to create initramfs if the supplied image is already a UKI
-if [[ "$KERNEL_INSTALL_IMAGE_TYPE" = "uki" ]]; then
+if [ "$KERNEL_INSTALL_IMAGE_TYPE" = "uki" ]; then
     exit 0
 fi
 
-if [[ "$KERNEL_INSTALL_UKI_GENERATOR" = "dracut" ]]; then
+if [ "$KERNEL_INSTALL_UKI_GENERATOR" = "dracut" ]; then
     # Rescue images currently not compatible with UKIs
     exit 0
-elif [[ "${KERNEL_INSTALL_INITRD_GENERATOR:-dracut}" != "dracut" ]]; then
+elif [ "${KERNEL_INSTALL_INITRD_GENERATOR:-dracut}" != "dracut" ]; then
     # We are not the initrd generator
     exit 0
 fi
@@ -28,19 +29,17 @@ fi
 dropindirs_sort() {
     suffix=$1
     shift
-    args=("$@")
     files=$(
-        while (($# > 0)); do
-            for i in "${1}"/*"${suffix}"; do
-                [[ -f $i ]] && echo "${i##*/}"
+        for d in "$@"; do
+            for i in "$d"/*"${suffix}"; do
+                [ -f "$i" ] && echo "${i##*/}"
             done
-            shift
         done | sort -Vu
     )
 
     for f in $files; do
-        for d in "${args[@]}"; do
-            if [[ -f "$d/$f" ]]; then
+        for d in "$@"; do
+            if [ -f "$d/$f" ]; then
                 echo "$d/$f"
                 continue 2
             fi
@@ -48,43 +47,45 @@ dropindirs_sort() {
     done
 }
 
-if [[ -f /etc/os-release ]]; then
+if [ -f /etc/os-release ]; then
     . /etc/os-release
-elif [[ -f /usr/lib/os-release ]]; then
+elif [ -f /usr/lib/os-release ]; then
     . /usr/lib/os-release
 fi
 
-[[ -n $PRETTY_NAME ]] || PRETTY_NAME="Linux $KERNEL_VERSION"
+[ -n "$PRETTY_NAME" ] || PRETTY_NAME="Linux $KERNEL_VERSION"
 
-if [[ ${KERNEL_INSTALL_MACHINE_ID+x} ]]; then
+if [ "${KERNEL_INSTALL_MACHINE_ID+x}" ]; then
     MACHINE_ID=$KERNEL_INSTALL_MACHINE_ID
-elif [[ -f /etc/machine-id ]]; then
+elif [ -f /etc/machine-id ]; then
     read -r MACHINE_ID < /etc/machine-id
 fi
 
-if ! [[ $MACHINE_ID ]]; then
+if [ -z "$MACHINE_ID" ]; then
     exit 0
 fi
 
 if [ -n "$KERNEL_INSTALL_CONF_ROOT" ]; then
-    if [ -f "$KERNEL_INSTALL_CONF_ROOT/cmdline" ]; then
-        read -r -d '' -a BOOT_OPTIONS < "$KERNEL_INSTALL_CONF_ROOT/cmdline"
-    fi
-elif [[ -f /etc/kernel/cmdline ]]; then
-    read -r -d '' -a BOOT_OPTIONS < /etc/kernel/cmdline
-elif [[ -f /usr/lib/kernel/cmdline ]]; then
-    read -r -d '' -a BOOT_OPTIONS < /usr/lib/kernel/cmdline
+    cmdline="$KERNEL_INSTALL_CONF_ROOT/cmdline"
+elif [ -f /etc/kernel/cmdline ]; then
+    cmdline=/etc/kernel/cmdline
+elif [ -f /usr/lib/kernel/cmdline ]; then
+    cmdline=/usr/lib/kernel/cmdline
 else
-    declare -a BOOT_OPTIONS
+    cmdline=/proc/cmdline
+fi
 
-    read -r -d '' -a line < /proc/cmdline
-    for i in "${line[@]}"; do
-        [[ ${i#initrd=*} != "$i" ]] && continue
-        BOOT_OPTIONS+=("$i")
+BOOT_OPTIONS=
+if [ -f "$cmdline" ]; then
+    for i in $(cat "$cmdline"); do
+        case $i in
+            initrd=*) ;;
+            *) BOOT_OPTIONS="${BOOT_OPTIONS}${BOOT_OPTIONS:+ }$i" ;;
+        esac
     done
 fi
 
-if [[ -d ${BOOT_DIR_ABS%/*} ]]; then
+if [ -d "${BOOT_DIR_ABS%/*}" ]; then
     BOOT_DIR="/${MACHINE_ID}/0-rescue"
     BOOT_ROOT=${BOOT_DIR_ABS%"$BOOT_DIR"}
     LOADER_ENTRY="$BOOT_ROOT/loader/entries/${MACHINE_ID}-0-rescue.conf"
@@ -102,55 +103,53 @@ ret=0
 
 case "$COMMAND" in
     add)
-        if [[ -f $LOADER_ENTRY ]] && [[ -f "$BOOT_DIR_ABS/$KERNEL" ]] \
-            && [[ -f "$BOOT_DIR_ABS/$INITRD" ]]; then
-            [[ $KERNEL_INSTALL_VERBOSE == 1 ]] \
+        if [ -f "$LOADER_ENTRY" ] && [ -f "$BOOT_DIR_ABS/$KERNEL" ] \
+            && [ -f "$BOOT_DIR_ABS/$INITRD" ]; then
+            [ "$KERNEL_INSTALL_VERBOSE" = 1 ] \
                 && echo "Skipping, there is already a rescue image generated with the same input parameters"
             exit 0
         fi
 
         # source our config dir
         for f in $(dropindirs_sort ".conf" "/etc/dracut.conf.d" "/usr/lib/dracut/dracut.conf.d" "/run/initramfs/dracut.conf.d"); do
-            if [[ -e $f ]]; then
+            if [ -e "$f" ]; then
                 # shellcheck disable=SC1090
                 . "$f"
             fi
         done
 
-        if [[ $dracut_rescue_image != "yes" ]]; then
-            [[ $KERNEL_INSTALL_VERBOSE == 1 ]] \
+        if [ "$dracut_rescue_image" != "yes" ]; then
+            [ "$KERNEL_INSTALL_VERBOSE" = 1 ] \
                 && echo "Skipping, 'dracut_rescue_image' not set to 'yes' in any dracut configuration file"
             exit 0
         fi
 
-        [[ -d $BOOT_DIR_ABS ]] || mkdir -p "$BOOT_DIR_ABS"
+        [ -d "$BOOT_DIR_ABS" ] || mkdir -p "$BOOT_DIR_ABS"
 
         if ! cp --reflink=auto "$KERNEL_IMAGE" "$BOOT_DIR_ABS/$KERNEL"; then
             echo "Can't copy '$KERNEL_IMAGE to '$BOOT_DIR_ABS/$KERNEL'!" >&2
         fi
 
-        if [[ ! -f "$BOOT_DIR_ABS/$INITRD" ]]; then
-            # shellcheck disable=SC2046
-            dracut -f \
-                --add-confdir rescue \
-                $([[ $KERNEL_INSTALL_VERBOSE == 1 ]] && echo --verbose) \
-                --kver "$KERNEL_VERSION" \
-                "$BOOT_DIR_ABS/$INITRD"
-            ((ret += $?))
+        if [ ! -f "$BOOT_DIR_ABS/$INITRD" ]; then
+            set -- dracut -f --add-confdir rescue
+            [ "$KERNEL_INSTALL_VERBOSE" = 1 ] && set -- "$@" --verbose
+            set -- "$@" --kver "$KERNEL_VERSION" "$BOOT_DIR_ABS/$INITRD"
+            "$@"
+            ret=$((ret + $?))
         fi
 
-        [[ $KERNEL_INSTALL_VERBOSE == 1 ]] && echo "Creating $LOADER_ENTRY"
-        if [[ ${BOOT_DIR_ABS} != "/boot" ]]; then
+        [ "$KERNEL_INSTALL_VERBOSE" = 1 ] && echo "Creating $LOADER_ENTRY"
+        if [ "$BOOT_DIR_ABS" != "/boot" ]; then
             {
                 echo "title      $PRETTY_NAME - Rescue Image"
                 echo "version    $KERNEL_VERSION"
                 echo "machine-id $MACHINE_ID"
-                echo "options    ${BOOT_OPTIONS[*]}"
+                echo "options    $BOOT_OPTIONS"
                 echo "linux      $BOOT_DIR/linux"
                 echo "initrd     $BOOT_DIR/initrd"
             } > "$LOADER_ENTRY"
         else
-            if [[ -e "${BLS_DIR}/${MACHINE_ID}-${KERNEL_VERSION}.conf" ]]; then
+            if [ -e "${BLS_DIR}/${MACHINE_ID}-${KERNEL_VERSION}.conf" ]; then
                 cp -aT "${BLS_DIR}/${MACHINE_ID}-${KERNEL_VERSION}.conf" "$LOADER_ENTRY"
             else
                 cp -aT "${KERNEL_IMAGE%/*}/bls.conf" "$LOADER_ENTRY"
@@ -158,7 +157,7 @@ case "$COMMAND" in
             sed -i "s/${KERNEL_VERSION}/0-rescue-${MACHINE_ID}/" "$LOADER_ENTRY"
         fi
 
-        ((ret += $?))
+        ret=$((ret + $?))
         ;;
 
     remove)
diff --git a/modules.d/45net-lib/net-lib.sh b/modules.d/45net-lib/net-lib.sh
index a0b8740..5365c2d 100755
--- a/modules.d/45net-lib/net-lib.sh
+++ b/modules.d/45net-lib/net-lib.sh
@@ -756,7 +756,7 @@ linkup() {
     wait_for_if_link "$@" 2> /dev/null && ip link set "$@" up 2> /dev/null && wait_for_if_up "$@" 2> /dev/null
 }
 
-type hostname > /dev/null 2>&1 \
+command -v hostname > /dev/null 2>&1 \
     || hostname() {
         cat /proc/sys/kernel/hostname
     }
diff --git a/modules.d/45plymouth/plymouth-newroot.sh b/modules.d/45plymouth/plymouth-newroot.sh
index 29c56e9..7409dee 100755
--- a/modules.d/45plymouth/plymouth-newroot.sh
+++ b/modules.d/45plymouth/plymouth-newroot.sh
@@ -1,5 +1,5 @@
 #!/bin/sh
 
-if type plymouth > /dev/null 2>&1 && [ -z "${DRACUT_SYSTEMD-}" ]; then
+if command -v plymouth > /dev/null 2>&1 && [ -z "${DRACUT_SYSTEMD-}" ]; then
     plymouth --newroot="$NEWROOT"
 fi
diff --git a/modules.d/45plymouth/plymouth-pretrigger.sh b/modules.d/45plymouth/plymouth-pretrigger.sh
index 869a119..b28b4f5 100755
--- a/modules.d/45plymouth/plymouth-pretrigger.sh
+++ b/modules.d/45plymouth/plymouth-pretrigger.sh
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-if type plymouthd > /dev/null 2>&1 && [ -z "${DRACUT_SYSTEMD-}" ]; then
+if command -v plymouthd > /dev/null 2>&1 && [ -z "${DRACUT_SYSTEMD-}" ]; then
     if getargbool 1 plymouth.enable && getargbool 1 rd.plymouth; then
         # first trigger graphics subsystem
         udevadm trigger --action=add --attr-match=class=0x030000 > /dev/null 2>&1
diff --git a/modules.d/70crypt-lib/crypt-lib.sh b/modules.d/70crypt-lib/crypt-lib.sh
index 82a672f..c065d7e 100755
--- a/modules.d/70crypt-lib/crypt-lib.sh
+++ b/modules.d/70crypt-lib/crypt-lib.sh
@@ -106,7 +106,7 @@ ask_for_password() {
     {
         flock -s 9
         # Prompt for password with plymouth, if installed and running.
-        if type plymouth > /dev/null 2>&1 && plymouth --ping 2> /dev/null; then
+        if command -v plymouth > /dev/null 2>&1 && plymouth --ping 2> /dev/null; then
             plymouth ask-for-password \
                 --prompt "$ply_prompt" --number-of-tries="$ply_tries" \
                 --command="$ply_cmd"
diff --git a/modules.d/70dmsquash-live/dmsquash-live-root.sh b/modules.d/70dmsquash-live/dmsquash-live-root.sh
index 3702a91..93b6f45 100755
--- a/modules.d/70dmsquash-live/dmsquash-live-root.sh
+++ b/modules.d/70dmsquash-live/dmsquash-live-root.sh
@@ -73,7 +73,7 @@ if [ ! -f "$livedev" ]; then
     fi
     getarg rd.live.check || check=""
     if [ -n "$check" ]; then
-        type plymouth > /dev/null 2>&1 && plymouth --hide-splash
+        command -v plymouth > /dev/null 2>&1 && plymouth --hide-splash
         if [ -n "${DRACUT_SYSTEMD-}" ]; then
             p=$(dev_unit_name "$check_dev")
             systemctl start checkisomd5@"${p}".service
@@ -86,7 +86,7 @@ if [ ! -f "$livedev" ]; then
             die "Media check failed!"
             exit 1
         fi
-        type plymouth > /dev/null 2>&1 && plymouth --show-splash
+        command -v plymouth > /dev/null 2>&1 && plymouth --show-splash
     fi
 fi
 
@@ -234,7 +234,7 @@ do_live_overlay() {
          Press [Enter] to continue.'
             printf "\n\n\n\n%s\n\n\n" "${m}" > /dev/kmsg
             if [ -n "${DRACUT_SYSTEMD-}" ]; then
-                if type plymouth > /dev/null 2>&1 && plymouth --ping; then
+                if command -v plymouth > /dev/null 2>&1 && plymouth --ping; then
                     if getargbool 0 rhgb || getargbool 0 splash; then
                         m='>>>
 >>>
@@ -257,7 +257,7 @@ do_live_overlay() {
                     systemd-ask-password --timeout=0 "${m}"
                 fi
             else
-                type plymouth > /dev/null 2>&1 && plymouth --ping && plymouth --quit
+                command -v plymouth > /dev/null 2>&1 && plymouth --ping && plymouth --quit
                 printf '\n\n%s' "$m"
                 read -r _
             fi
diff --git a/modules.d/70fs-lib/fs-lib.sh b/modules.d/70fs-lib/fs-lib.sh
index e11f3c1..a450aa5 100755
--- a/modules.d/70fs-lib/fs-lib.sh
+++ b/modules.d/70fs-lib/fs-lib.sh
@@ -43,17 +43,17 @@ fsck_able() {
             return 1
             ;;
         ext?)
-            type e2fsck > /dev/null 2>&1 \
+            command -v e2fsck > /dev/null 2>&1 \
                 && _drv="fsck_drv_com e2fsck" \
                 && return 0
             ;;
         f2fs)
-            type fsck.f2fs > /dev/null 2>&1 \
+            command -v fsck.f2fs > /dev/null 2>&1 \
                 && _drv="fsck_drv_com fsck.f2fs" \
                 && return 0
             ;;
         jfs)
-            type jfs_fsck > /dev/null 2>&1 \
+            command -v jfs_fsck > /dev/null 2>&1 \
                 && _drv="fsck_drv_com jfs_fsck" \
                 && return 0
             ;;
@@ -69,7 +69,7 @@ fsck_able() {
                 && return 0
             ;;
         *)
-            type fsck > /dev/null 2>&1 \
+            command -v fsck > /dev/null 2>&1 \
                 && _drv="fsck_drv_std fsck" \
                 && return 0
             ;;
@@ -250,7 +250,7 @@ write_fs_tab() {
         return
     fi
 
-    if type systemctl > /dev/null 2> /dev/null; then
+    if command -v systemctl > /dev/null 2> /dev/null; then
         systemctl daemon-reload
         systemctl --no-block start initrd-root-fs.target
     fi
diff --git a/modules.d/70livenet/livenet-generator.sh b/modules.d/70livenet/livenet-generator.sh
index 45a4001..c79321b 100755
--- a/modules.d/70livenet/livenet-generator.sh
+++ b/modules.d/70livenet/livenet-generator.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 command -v getarg > /dev/null || . /lib/dracut-lib.sh
 
@@ -74,7 +74,7 @@ ROOTFLAGS="$(getarg rootflags)"
     else
         echo "What=/dev/mapper/live-rw"
         [ -n "$ROOTFLAGS" ] && echo "Options=${ROOTFLAGS}"
-        _dev=$'dev-mapper-live\\x2drw'
+        _dev='dev-mapper-live\x2drw'
     fi
 } > "$GENERATOR_DIR"/sysroot.mount
 
diff --git a/modules.d/70livenet/module-setup.sh b/modules.d/70livenet/module-setup.sh
index 3ec6baf..9465213 100755
--- a/modules.d/70livenet/module-setup.sh
+++ b/modules.d/70livenet/module-setup.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 # module-setup.sh for livenet
 
 # called by dracut
@@ -8,7 +8,7 @@ check() {
 
 # called by dracut
 depends() {
-    echo network url-lib dmsquash-live img-lib bash initqueue
+    echo network url-lib dmsquash-live img-lib initqueue
     return 0
 }
 
diff --git a/modules.d/73zipl/install_zipl_cmdline.sh b/modules.d/73zipl/install_zipl_cmdline.sh
index 1a666da..59af087 100755
--- a/modules.d/73zipl/install_zipl_cmdline.sh
+++ b/modules.d/73zipl/install_zipl_cmdline.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 DEV="$1"
 MNT=/boot/zipl
@@ -22,7 +22,7 @@ if [ -f ${MNT}/dracut-cmdline.conf ]; then
 fi
 
 if [ -f ${MNT}/active_devices.txt ]; then
-    while read -r dev _ || [[ $dev ]]; do
+    while read -r dev _ || [ -n "$dev" ]; do
         [ "$dev" = "#" ] || [ "$dev" = "" ] && continue
         cio_ignore -r "$dev"
     done < ${MNT}/active_devices.txt
diff --git a/modules.d/73zipl/module-setup.sh b/modules.d/73zipl/module-setup.sh
index 2772ec6..b1facb3 100755
--- a/modules.d/73zipl/module-setup.sh
+++ b/modules.d/73zipl/module-setup.sh
@@ -1,9 +1,8 @@
-#!/bin/bash
+#!/bin/sh
 # -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
 # ex: ts=8 sw=4 sts=4 et filetype=sh
 
 get_boot_zipl_dev() {
-    local _boot_zipl
     _boot_zipl=$(sed -n -e '/^[[:space:]]*#/d' -e 's/\(.*\)\w*\/boot\/zipl.*/\1/p' "${dracutsysrootdir-}"/etc/fstab)
     printf "%s" "$(trim "$_boot_zipl")"
 }
@@ -19,13 +18,11 @@ check() {
 
 # called by dracut
 depends() {
-    echo bash initqueue
+    echo initqueue
 }
 
 # called by dracut
 installkernel() {
-    local _boot_zipl
-
     _boot_zipl=$(get_boot_zipl_dev)
     if [ -n "$_boot_zipl" ]; then
         eval "$(blkid -s TYPE -o udev "${_boot_zipl}")"
@@ -42,8 +39,6 @@ installkernel() {
 
 # called by dracut
 cmdline() {
-    local _boot_zipl
-
     _boot_zipl=$(get_boot_zipl_dev)
     if [ -n "$_boot_zipl" ]; then
         printf "%s" " rd.zipl=${_boot_zipl}"
@@ -56,10 +51,9 @@ install() {
 
     inst_hook cmdline 91 "$moddir/parse-zipl.sh"
     inst_script "${moddir}/install_zipl_cmdline.sh" /sbin/install_zipl_cmdline.sh
-    if [[ $hostonly_cmdline == "yes" ]]; then
-        local _zipl
+    if [ "$hostonly_cmdline" = "yes" ]; then
         _zipl=$(cmdline)
 
-        [[ $_zipl ]] && printf "%s\n" "$_zipl" > "${initdir}/etc/cmdline.d/19-zipl.conf"
+        [ -n "$_zipl" ] && printf "%s\n" "$_zipl" > "${initdir}/etc/cmdline.d/19-zipl.conf"
     fi
 }
diff --git a/modules.d/74znet/module-setup.sh b/modules.d/74znet/module-setup.sh
index 6c340a6..59ef3a2 100755
--- a/modules.d/74znet/module-setup.sh
+++ b/modules.d/74znet/module-setup.sh
@@ -11,7 +11,6 @@ check() {
 
 # called by dracut
 depends() {
-    echo bash
     return 0
 }
 
diff --git a/modules.d/74znet/parse-ccw.sh b/modules.d/74znet/parse-ccw.sh
index acdd63e..473e355 100755
--- a/modules.d/74znet/parse-ccw.sh
+++ b/modules.d/74znet/parse-ccw.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 znet_base_args="--no-settle --yes --no-root-update --force"
 
@@ -48,14 +48,25 @@ for ccw_arg in $(getargs rd.znet); do
 done
 
 for ifname in $(getargs rd.znet_ifname); do
-    IFS=: read -r ifname_if ifname_subchannels _rest <<< "$ifname"
+    ifname_if=${ifname%%:*}
+    ifname_subchannels=${ifname#*:}
+    if [ "$ifname_subchannels" = "$ifname" ]; then
+        _rest=invalid
+    else
+        _rest=${ifname_subchannels#*:}
+        if [ "$_rest" = "$ifname_subchannels" ]; then
+            _rest=
+        else
+            ifname_subchannels=${ifname_subchannels%%:*}
+        fi
+    fi
     if [ -z "$ifname_if" ] || [ -z "$ifname_subchannels" ] || [ -n "$_rest" ]; then
         warn "Invalid arguments for rd.znet_ifname="
     else
         {
-            ifname_subchannels="${ifname_subchannels//,/|}"
+            ifname_subchannels=$(printf '%s' "$ifname_subchannels" | tr ',' '|')
             # sanitize for use in udev label: replace non-word characters by _
-            ifname_if_label="${ifname_if//[^[:word:]]/_}"
+            ifname_if_label=$(printf '%s' "$ifname_if" | sed 's/[^[:alnum:]_]/_/g')
 
             echo "ACTION!=\"add|change\", GOTO=\"ccw_ifname_${ifname_if_label}_end\""
             echo "ATTR{type}!=\"1\", GOTO=\"ccw_ifname_${ifname_if_label}_end\""
diff --git a/modules.d/77dracut-systemd/dracut-emergency.sh b/modules.d/77dracut-systemd/dracut-emergency.sh
index a427a8f..65f8232 100755
--- a/modules.d/77dracut-systemd/dracut-emergency.sh
+++ b/modules.d/77dracut-systemd/dracut-emergency.sh
@@ -8,7 +8,7 @@ command -v getarg > /dev/null || . /lib/dracut-lib.sh
 
 source_conf /etc/conf.d
 
-type plymouth > /dev/null 2>&1 && plymouth quit
+command -v plymouth > /dev/null 2>&1 && plymouth quit
 
 export _rdshell_name="dracut" action="Boot" hook="emergency"
 _emergency_action=$(getarg rd.emergency)
diff --git a/modules.d/80base/dracut-dev-lib.sh b/modules.d/80base/dracut-dev-lib.sh
index bc640f7..1f30438 100755
--- a/modules.d/80base/dracut-dev-lib.sh
+++ b/modules.d/80base/dracut-dev-lib.sh
@@ -83,7 +83,7 @@ set_systemd_timeout_for_dev() {
             echo "JobTimeoutSec=$_timeout"
             echo "JobRunningTimeoutSec=$_timeout"
         } > "${PREFIX-}/etc/systemd/system/${_name}.device.d/timeout.conf"
-        type mark_hostonly > /dev/null 2>&1 && mark_hostonly /etc/systemd/system/"${_name}".device.d/timeout.conf
+        command -v mark_hostonly > /dev/null 2>&1 && mark_hostonly /etc/systemd/system/"${_name}".device.d/timeout.conf
         _needreload=1
     fi
 
@@ -110,7 +110,7 @@ wait_for_dev() {
 
     _name="$(str_replace "$1" '/' '\x2f')"
 
-    type mark_hostonly > /dev/null 2>&1 && mark_hostonly "$hookdir/initqueue/finished/devexists-${_name}.sh"
+    command -v mark_hostonly > /dev/null 2>&1 && mark_hostonly "$hookdir/initqueue/finished/devexists-${_name}.sh"
 
     [ -e "${PREFIX-}$hookdir/initqueue/finished/devexists-${_name}.sh" ] && return 0
 
@@ -127,7 +127,7 @@ wait_for_dev() {
     if ! [ -L "${PREFIX-}/etc/systemd/system/initrd.target.wants/${_unit}" ]; then
         [ -d "${PREFIX-}"/etc/systemd/system/initrd.target.wants ] || mkdir -p "${PREFIX-}"/etc/systemd/system/initrd.target.wants
         ln -s ../"${_unit}" "${PREFIX-}/etc/systemd/system/initrd.target.wants/${_unit}"
-        type mark_hostonly > /dev/null 2>&1 && mark_hostonly /etc/systemd/system/initrd.target.wants/"${_unit}"
+        command -v mark_hostonly > /dev/null 2>&1 && mark_hostonly /etc/systemd/system/initrd.target.wants/"${_unit}"
         _needreload=1
     fi
 
diff --git a/modules.d/86shutdown/shutdown.sh b/modules.d/86shutdown/shutdown.sh
index fd15ab5..cb9828c 100755
--- a/modules.d/86shutdown/shutdown.sh
+++ b/modules.d/86shutdown/shutdown.sh
@@ -35,7 +35,7 @@ if [ "$ACTION" = "kexec" ] && ! command -v kexec > /dev/null 2>&1; then
     for p in /usr/sbin /usr/bin /sbin /bin; do
         cp -a /oldroot/${p}/kexec $p > /dev/null 2>&1 && break
     done
-    hash kexec
+    command -v kexec > /dev/null 2>&1
 fi
 
 trap "emergency_shell --shutdown shutdown Signal caught!" 0
@@ -152,7 +152,7 @@ while [ $_cnt -le 40 ]; do
 done
 [ $_cnt -ge 40 ] && _check_shutdown final
 
-if type plymouth > /dev/null 2>&1; then
+if command -v plymouth > /dev/null 2>&1; then
     plymouth --hide-splash
 elif [ -x /oldroot/bin/plymouth ]; then
     /oldroot/bin/plymouth --hide-splash
diff --git a/tools/release.sh b/tools/release.sh
index 92dad34..f14fc62 100755
--- a/tools/release.sh
+++ b/tools/release.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 # clog might be installed in the user home
 export PATH="$PATH:~/.cargo/bin"
@@ -31,7 +31,7 @@ cat _CONTRIBUTORS >> CONTRIBUTORS.md
 make AUTHORS
 
 # Update the contributors list in NEWS.md
-if ! type -p clog &> /dev/null; then
+if ! command -v clog > /dev/null 2>&1; then
     cargo install clog-cli --version 0.9.3
 fi
 head --lines=2 NEWS.md > NEWS_header.md