diff --git a/cdist/conf/type/__hwclock/explorer/adjtime_mode b/cdist/conf/type/__hwclock/explorer/adjtime_mode
new file mode 100755
index 00000000..2b27bedc
--- /dev/null
+++ b/cdist/conf/type/__hwclock/explorer/adjtime_mode
@@ -0,0 +1,28 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# cdist is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+# Prints the clock mode read from the /etc/adjtime file, if present.
+#
+
+# not all operating systems use an adjfile
+test -f /etc/adjtime || exit 0
+
+# 3rd line is clock mode
+# adjtime(5) https://man7.org/linux/man-pages/man5/adjtime.5.html
+sed -n 3p /etc/adjtime
diff --git a/cdist/conf/type/__hwclock/explorer/timedatectl_localrtc b/cdist/conf/type/__hwclock/explorer/timedatectl_localrtc
new file mode 100755
index 00000000..8239122e
--- /dev/null
+++ b/cdist/conf/type/__hwclock/explorer/timedatectl_localrtc
@@ -0,0 +1,27 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# cdist is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+# Prints the LocalRTC property using timedatectl on systemd-based systems.
+#
+
+command -v timedatectl >/dev/null 2>&1 || exit 0
+
+# NOTE: Older versions of timedatectl do not support `timedatectl show'
+timedatectl --no-pager status \
+| awk -F': ' '$1 ~ "RTC in local TZ$" { sub(/[ \t]*$/, "", $2); print $2 }'
diff --git a/cdist/conf/type/__hwclock/gencode-remote b/cdist/conf/type/__hwclock/gencode-remote
new file mode 100755
index 00000000..5995fb23
--- /dev/null
+++ b/cdist/conf/type/__hwclock/gencode-remote
@@ -0,0 +1,62 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera@ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# cdist is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+mode=$(cat "${__object:?}/parameter/mode")
+
+timedatectl_localrtc=$(cat "${__object:?}/explorer/timedatectl_localrtc")
+adjtime_mode=$(cat "${__object:?}/explorer/adjtime_mode")
+
+
+case ${mode}
+in
+	(localtime)
+		adjtime_str=LOCAL
+		local_rtc_str=yes
+		;;
+	(UTC|utc)
+		adjtime_str=UTC
+		local_rtc_str=no
+		;;
+	(*)
+		printf 'Invalid value for --mode: %s\n' "${mode}" >&2
+		printf 'Acceptable values are: localtime, utc.\n' >&2
+		exit 1
+esac
+
+
+if test -n "${timedatectl_localrtc}"
+then
+	# systemd
+	timedatectl_should=${local_rtc_str}
+	if test "${timedatectl_localrtc}" != "${timedatectl_should}"
+	then
+		printf 'timedatectl set-local-rtc %s\n' "${timedatectl_should}"
+	fi
+elif test -n "${adjtime_mode}"
+then
+	# others (update /etc/adjtime if present)
+	if test "${adjtime_mode}" != "${adjtime_str}"
+	then
+		# Update /etc/adjtime (3rd line is clock mode)
+		# adjtime(5) https://man7.org/linux/man-pages/man5/adjtime.5.html
+		# FIXME: Should maybe add third line if adjfile only contains two lines
+		printf "sed -i '3c\\\\\\n%s\\n' /etc/adjtime\\n" "${adjtime_str}"
+	fi
+fi
diff --git a/cdist/conf/type/__hwclock/man.rst b/cdist/conf/type/__hwclock/man.rst
new file mode 100644
index 00000000..65eb648f
--- /dev/null
+++ b/cdist/conf/type/__hwclock/man.rst
@@ -0,0 +1,63 @@
+cdist-type__hwclock(7)
+======================
+
+NAME
+----
+cdist-type__hwclock - Manage the hardware real time clock.
+
+
+DESCRIPTION
+-----------
+This type can be used to control how the hardware clock is used by the operating
+system.
+
+
+REQUIRED PARAMETERS
+-------------------
+mode
+    What mode the hardware clock is in.
+
+    Acceptable values:
+
+    localtime
+        The hardware clock is set to local time (common for systems also running
+        Windows.)
+    UTC
+        The hardware clock is set to UTC (common on UNIX systems.)
+
+
+OPTIONAL PARAMETERS
+-------------------
+None.
+
+
+BOOLEAN PARAMETERS
+------------------
+None.
+
+
+EXAMPLES
+--------
+
+.. code-block:: sh
+
+    # Make the operating system treat the time read from the hwclock as UTC.
+    __hwclock --mode UTC
+
+
+SEE ALSO
+--------
+:strong:`hwclock`\ (8)
+
+
+AUTHORS
+-------
+Dennis Camera <dennis.camera@ssrq-sds-fds.ch>
+
+
+COPYING
+-------
+Copyright \(C) 2020 Dennis Camera. You can redistribute it
+and/or modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation, either version 3 of the
+License, or (at your option) any later version.
diff --git a/cdist/conf/type/__hwclock/manifest b/cdist/conf/type/__hwclock/manifest
new file mode 100755
index 00000000..7d9ab88f
--- /dev/null
+++ b/cdist/conf/type/__hwclock/manifest
@@ -0,0 +1,222 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera@ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# cdist is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# TODO: Consider supporting BADYEAR
+
+os=$(cat "${__global:?}/explorer/os")
+mode=$(cat "${__object:?}/parameter/mode")
+
+has_systemd_timedatectl=$(test -s "${__object:?}/explorer/timedatectl_localrtc" && echo true || echo false)
+
+
+case ${mode}
+in
+	(localtime)
+		local_clock=true
+		;;
+	(UTC|utc)
+		local_clock=false
+		;;
+	(*)
+		printf 'Invalid value for --mode: %s\n' "${mode}" >&2
+		printf 'Acceptable values are: UTC, localtime.\n' >&2
+		exit 1
+esac
+
+
+case ${os}
+in
+	(alpine|gentoo)
+		if ! $has_systemd_timedatectl
+		then
+			# NOTE: Gentoo also supports systemd, in which case /etc/conf.d is
+			#       not used. So we check for systemd presence here and only
+			#       update /etc/conf.d if systemd is not installed.
+			# https://wiki.gentoo.org/wiki/System_time#Hardware_clock
+
+			export CDIST_ORDER_DEPENDENCY=true
+			__file /etc/conf.d/hwclock --state present \
+				--owner root --group root --mode 0644
+			__key_value /etc/conf.d/hwclock:clock \
+				--file /etc/conf.d/hwclock \
+				--key clock \
+				--delimiter '=' --exact_delimiter \
+				--value "\"$($local_clock && echo local || echo UTC)\""
+			unset CDIST_ORDER_DEPENDENCY
+		fi
+		;;
+	(centos|fedora|redhat|scientific)
+		os_version=$(cat "${__global:?}/explorer/os_version")
+		os_major=$(expr "${os_version}" : '.* release \([0-9]*\)')
+		case ${os}
+		in
+			(centos|scientific)
+				update_sysconfig=$(test "${os_major}" -lt 6 && echo true || echo false)
+				;;
+			(fedora)
+				update_sysconfig=$(test "${os_major}" -lt 10 && echo true || echo false)
+				;;
+			(redhat|*)
+				case ${os_version}
+				in
+					('Red Hat Enterprise Linux'*)
+						update_sysconfig=$(test "${os_major}" -lt 6 && echo true || echo false)
+						;;
+					('Red Hat Linux'*)
+						update_sysconfig=true
+						;;
+					(*)
+						printf 'Could not determine Red Hat distribution.\n' >&2
+						printf "Please contribute an implementation for it if you can.\n" >&2
+						exit 1
+						;;
+				esac
+				;;
+		esac
+
+		if ${update_sysconfig:?}
+		then
+			export CDIST_ORDER_DEPENDENCY=true
+			__file /etc/sysconfig/clock --state present \
+				--owner root --group root --mode 0644
+			__key_value /etc/sysconfig/clock:UTC \
+				--file /etc/sysconfig/clock \
+				--key UTC \
+				--delimiter '=' --exact_delimiter \
+				--value "$($local_clock && echo false || echo true)"
+			unset CDIST_ORDER_DEPENDENCY
+		fi
+		;;
+	(debian|devuan|ubuntu)
+		os_major=$(sed 's/[^0-9].*$//' "${__global:?}/explorer/os_version")
+
+		case ${os}
+		in
+			(debian)
+				if test "${os_major}" -ge 7
+				then
+					update_rcS=false
+				elif test "${os_major}" -ge 3
+				then
+					update_rcS=true
+				else
+					# Debian 2.2 should be supportable using rcS.
+					# Debian 2.1 uses the ancient GMT key.
+					# Debian 1.3 does not have rcS.
+					printf "Your operating system (Debian %s) is currently not supported by this type (%s)\n" \
+						"$(cat "${__global:?}/explorer/os_version")" "${__type##*/}" >&2
+					printf "Please contribute an implementation for it if you can.\n" >&2
+					exit 1
+				fi
+				;;
+			(devuan)
+				update_rcS=false
+				;;
+			(ubuntu)
+				update_rcS=$(test "${os_major}" -lt 16 && echo true || echo false)
+				;;
+		esac
+
+		if ${update_rcS}
+		then
+			export CDIST_ORDER_DEPENDENCY=true
+			__file /etc/default/rcS --state present \
+				--owner root --group root --mode 0644
+			__key_value /etc/default/rcS:UTC \
+				--file /etc/default/rcS \
+				--key UTC \
+				--delimiter '=' --exact_delimiter \
+				--value "$($local_clock && echo no || echo yes)"
+			unset CDIST_ORDER_DEPENDENCY
+		fi		  
+		;;
+	(freebsd)
+		# cf. adjkerntz(8)
+		__file /etc/wall_cmos_clock \
+			--state "$($local_clock && echo present || echo absent)" \
+			--owner root --group wheel --mode 0444
+		;;
+	(netbsd)
+		# https://wiki.netbsd.org/guide/boot/#index9h2
+		__key_value /etc/rc.conf:rtclocaltime \
+			--file /etc/rc.conf \
+			--key rtclocaltime \
+			--delimiter '=' --exact_delimiter \
+			--value "$($local_clock && echo YES || echo NO)"
+		;;
+	(slackware)
+		__file /etc/hardwareclock --owner root --group root --mode 0644 \
+			--source - <<-EOF
+		# /etc/hardwareclock
+		#
+		# Tells how the hardware clock time is stored.
+		# This file is managed by cdist.
+
+		$($local_clock && echo localtime || echo UTC)
+		EOF
+		;;
+	(suse)
+		if test -s "${__global:?}/explorer/os_release"
+		then
+			# shellcheck source=/dev/null
+			os_version=$(. "${__global:?}/explorer/os_release" && echo "${VERSION}")
+		else
+			os_version=$(sed -n 's/^VERSION\ *=\ *//p' "${__global:?}/explorer/os_version")
+		fi
+		os_major=$(expr "${os_version}" : '\([0-9]\{1,\}\)')
+
+		# TODO: Consider using `yast2 timezone set hwclock' instead
+		if expr "${os_major}" \< 12
+		then
+			# Starting with SuSE 12 (first systemd-based version)
+			# /etc/sysconfig/clock does not contain the HWCLOCK line
+			# anymore.
+			# With SuSE 13, it has been reduced to TIMEZONE configuration.
+			__key_value /etc/sysconfig/clock:HWCLOCK \
+				--file /etc/sysconfig/clock \
+				--delimiter '=' --exact_delimiter \
+				--key HWCLOCK \
+				--value "$($local_clock && echo '"--localtime"' || echo '"-u"')"
+		fi
+		;;
+	(void)
+		export CDIST_ORDER_DEPENDENCY=true
+		__file /etc/rc.conf \
+			--owner root --group root --mode 0644 \
+			--state present
+		__key_value /etc/rc.conf:HARDWARECLOCK \
+			--file /etc/rc.conf \
+			--delimiter '=' --exact_delimiter \
+			--key HARDWARECLOCK \
+			--value "\"$($local_clock && echo localtime || echo UTC)\""
+		unset CDIST_ORDER_DEPENDENCY
+		;;
+	(*)
+		if ! $has_systemd_timedatectl
+		then
+			printf "Your operating system (%s) is currently not supported by this type (%s)\n" "$os" "${__type##*/}" >&2
+			printf "Please contribute an implementation for it if you can.\n" >&2
+			exit 1
+		fi
+		;;
+esac
+
+# NOTE: timedatectl set-local-rtc for systemd is in gencode-remote
+# NOTE: /etc/adjtime is also updated in gencode-remote
diff --git a/cdist/conf/type/__hwclock/parameter/required b/cdist/conf/type/__hwclock/parameter/required
new file mode 100644
index 00000000..17ab372f
--- /dev/null
+++ b/cdist/conf/type/__hwclock/parameter/required
@@ -0,0 +1 @@
+mode
diff --git a/cdist/conf/type/__hwclock/singleton b/cdist/conf/type/__hwclock/singleton
new file mode 100644
index 00000000..e69de29b