diff --git a/cookbooks/base/cron-apt.rb b/cookbooks/base/cron-apt.rb
deleted file mode 100644
index 9083ce4..0000000
--- a/cookbooks/base/cron-apt.rb
+++ /dev/null
@@ -1,44 +0,0 @@
-# Install `cron-apt`:
-package 'cron-apt'
-
-# From here, we are going to set up `cron-apt` to
-# install the important security updates every day.
-remote_file '/etc/cron-apt/config' do
-  user 'root'
-
-  owner 'root'
-  group 'root'
-  mode  '644'
-end
-
-remote_file '/etc/cron-apt/action.d/3-download' do
-  user 'root'
-
-  owner 'root'
-  group 'root'
-  mode '644'
-end
-
-execute 'grep security /etc/apt/sources.list > /etc/apt/security.sources.list' do
-  user 'root'
-
-  not_if 'test -e /etc/apt/security.sources.list'
-end
-
-file '/var/log/cron-apt/log' do
-  user 'root'
-
-  content 'foo\n'
-
-  owner 'root'
-  group 'root'
-  mode '666'
-
-  not_if 'test -e /var/log/cron-apt/log'
-end
-
-execute '/usr/sbin/logrotate -f /etc/logrotate.d/cron-apt' do
-  user 'root'
-
-  not_if 'test -e /var/log/cron-apt/log'
-end
diff --git a/cookbooks/base/default.rb b/cookbooks/base/default.rb
index 1704b7a..caa17e2 100644
--- a/cookbooks/base/default.rb
+++ b/cookbooks/base/default.rb
@@ -39,8 +39,8 @@ include_recipe './packages.rb'
 # Lang Setting:
 include_recipe './lang.rb'
 
-# `cron-apt` settings:
-include_recipe './cron-apt.rb'
+# `unattended-upgrade` settings:
+include_recipe './unattended-upgrade.rb'
 
 # `ufw` configurations:
 include_recipe './ufw.rb'
diff --git a/cookbooks/base/files/etc/apt/apt.conf.d/20auto-upgrades b/cookbooks/base/files/etc/apt/apt.conf.d/20auto-upgrades
new file mode 100644
index 0000000..8d6d7c8
--- /dev/null
+++ b/cookbooks/base/files/etc/apt/apt.conf.d/20auto-upgrades
@@ -0,0 +1,2 @@
+APT::Periodic::Update-Package-Lists "1";
+APT::Periodic::Unattended-Upgrade "1";
diff --git a/cookbooks/base/files/etc/apt/apt.conf.d/50unattended-upgrades b/cookbooks/base/files/etc/apt/apt.conf.d/50unattended-upgrades
new file mode 100644
index 0000000..d31a4d2
--- /dev/null
+++ b/cookbooks/base/files/etc/apt/apt.conf.d/50unattended-upgrades
@@ -0,0 +1,131 @@
+// Automatically upgrade packages from these (origin:archive) pairs
+//
+// Note that in Ubuntu security updates may pull in new dependencies
+// from non-security sources (e.g. chromium). By allowing the release
+// pocket these get automatically pulled in.
+Unattended-Upgrade::Allowed-Origins {
+	"${distro_id}:${distro_codename}";
+	"${distro_id}:${distro_codename}-security";
+	// Extended Security Maintenance; doesn't necessarily exist for
+	// every release and this system may not have it installed, but if
+	// available, the policy for updates is such that unattended-upgrades
+	// should also install from here by default.
+	"${distro_id}ESMApps:${distro_codename}-apps-security";
+	"${distro_id}ESM:${distro_codename}-infra-security";
+//	"${distro_id}:${distro_codename}-updates";
+//	"${distro_id}:${distro_codename}-proposed";
+//	"${distro_id}:${distro_codename}-backports";
+};
+
+// Python regular expressions, matching packages to exclude from upgrading
+Unattended-Upgrade::Package-Blacklist {
+    // The following matches all packages starting with linux-
+//  "linux-";
+
+    // Use $ to explicitely define the end of a package name. Without
+    // the $, "libc6" would match all of them.
+//  "libc6$";
+//  "libc6-dev$";
+//  "libc6-i686$";
+
+    // Special characters need escaping
+//  "libstdc\+\+6$";
+
+    // The following matches packages like xen-system-amd64, xen-utils-4.1,
+    // xenstore-utils and libxenstore3.0
+//  "(lib)?xen(store)?";
+
+    // For more information about Python regular expressions, see
+    // https://docs.python.org/3/howto/regex.html
+};
+
+// This option controls whether the development release of Ubuntu will be
+// upgraded automatically. Valid values are "true", "false", and "auto".
+Unattended-Upgrade::DevRelease "auto";
+
+// This option allows you to control if on a unclean dpkg exit
+// unattended-upgrades will automatically run
+//   dpkg --force-confold --configure -a
+// The default is true, to ensure updates keep getting installed
+//Unattended-Upgrade::AutoFixInterruptedDpkg "true";
+
+// Split the upgrade into the smallest possible chunks so that
+// they can be interrupted with SIGTERM. This makes the upgrade
+// a bit slower but it has the benefit that shutdown while a upgrade
+// is running is possible (with a small delay)
+//Unattended-Upgrade::MinimalSteps "true";
+
+// Install all updates when the machine is shutting down
+// instead of doing it in the background while the machine is running.
+// This will (obviously) make shutdown slower.
+// Unattended-upgrades increases logind's InhibitDelayMaxSec to 30s.
+// This allows more time for unattended-upgrades to shut down gracefully
+// or even install a few packages in InstallOnShutdown mode, but is still a
+// big step back from the 30 minutes allowed for InstallOnShutdown previously.
+// Users enabling InstallOnShutdown mode are advised to increase
+// InhibitDelayMaxSec even further, possibly to 30 minutes.
+//Unattended-Upgrade::InstallOnShutdown "false";
+
+// Send email to this address for problems or packages upgrades
+// If empty or unset then no email is sent, make sure that you
+// have a working mail setup on your system. A package that provides
+// 'mailx' must be installed. E.g. "user@example.com"
+//Unattended-Upgrade::Mail "";
+
+// Set this value to one of:
+//    "always", "only-on-error" or "on-change"
+// If this is not set, then any legacy MailOnlyOnError (boolean) value
+// is used to chose between "only-on-error" and "on-change"
+//Unattended-Upgrade::MailReport "on-change";
+
+// Remove unused automatically installed kernel-related packages
+// (kernel images, kernel headers and kernel version locked tools).
+Unattended-Upgrade::Remove-Unused-Kernel-Packages "true";
+
+// Do automatic removal of newly unused dependencies after the upgrade
+Unattended-Upgrade::Remove-New-Unused-Dependencies "true";
+
+// Do automatic removal of unused packages after the upgrade
+// (equivalent to apt-get autoremove)
+Unattended-Upgrade::Remove-Unused-Dependencies "true";
+
+// Automatically reboot *WITHOUT CONFIRMATION* if
+//  the file /var/run/reboot-required is found after the upgrade
+Unattended-Upgrade::Automatic-Reboot "false";
+
+// Automatically reboot even if there are users currently logged in
+// when Unattended-Upgrade::Automatic-Reboot is set to true
+//Unattended-Upgrade::Automatic-Reboot-WithUsers "true";
+
+// If automatic reboot is enabled and needed, reboot at the specific
+// time instead of immediately
+//  Default: "now"
+//Unattended-Upgrade::Automatic-Reboot-Time "02:00";
+
+// Use apt bandwidth limit feature, this example limits the download
+// speed to 70kb/sec
+//Acquire::http::Dl-Limit "70";
+
+// Enable logging to syslog. Default is False
+// Unattended-Upgrade::SyslogEnable "false";
+
+// Specify syslog facility. Default is daemon
+// Unattended-Upgrade::SyslogFacility "daemon";
+
+// Download and install upgrades only on AC power
+// (i.e. skip or gracefully stop updates on battery)
+// Unattended-Upgrade::OnlyOnACPower "true";
+
+// Download and install upgrades only on non-metered connection
+// (i.e. skip or gracefully stop updates on a metered connection)
+// Unattended-Upgrade::Skip-Updates-On-Metered-Connections "true";
+
+// Verbose logging
+// Unattended-Upgrade::Verbose "false";
+
+// Print debugging information both in unattended-upgrades and
+// in unattended-upgrade-shutdown
+// Unattended-Upgrade::Debug "false";
+
+// Allow package downgrade if Pin-Priority exceeds 1000
+// Unattended-Upgrade::Allow-downgrade "false";
diff --git a/cookbooks/base/unattended-upgrade.rb b/cookbooks/base/unattended-upgrade.rb
new file mode 100644
index 0000000..4ab6b59
--- /dev/null
+++ b/cookbooks/base/unattended-upgrade.rb
@@ -0,0 +1,56 @@
+case run_command('grep VERSION_ID /etc/os-release | awk -F\" \'{print $2}\'').stdout.chomp
+when "18.04"
+  # Install `cron-apt`:
+  package 'cron-apt'
+
+  # From here, we are going to set up `cron-apt` to
+  # install the important security updates every day.
+  remote_file '/etc/cron-apt/config' do
+    user 'root'
+
+    owner 'root'
+    group 'root'
+    mode  '644'
+  end
+
+  remote_file '/etc/cron-apt/action.d/3-download' do
+    user 'root'
+
+    owner 'root'
+    group 'root'
+    mode '644'
+  end
+
+  execute 'grep security /etc/apt/sources.list > /etc/apt/security.sources.list' do
+    user 'root'
+
+    not_if 'test -e /etc/apt/security.sources.list'
+  end
+
+  file '/var/log/cron-apt/log' do
+    user 'root'
+
+    content 'foo\n'
+
+    owner 'root'
+    group 'root'
+    mode '666'
+
+    not_if 'test -e /var/log/cron-apt/log'
+  end
+
+  execute '/usr/sbin/logrotate -f /etc/logrotate.d/cron-apt' do
+    user 'root'
+
+    not_if 'test -e /var/log/cron-apt/log'
+  end
+
+when '20.04'
+  %w(20auto-upgrades 50unattended-upgrades).each do |conf|
+    remote_file "/etc/apt/apt.conf.d/#{conf}" do
+      owner 'root'
+      group 'root'
+      mode  '644'
+    end
+  end
+end