diff --git a/data/common/common.yaml b/data/common/common.yaml
--- a/data/common/common.yaml
+++ b/data/common/common.yaml
@@ -2554,6 +2554,8 @@
 swh::deploy::worker::loader_opam::user: swhworker
 swh::deploy::worker::loader_opam::group: swhworker
 swh::deploy::worker::opam::root_directory: /tmp/opam/
+
+# Keep opam.ocaml.org entry as the first one which is the default repository
 swh::deploy::worker::opam::instances:
   opam.ocaml.org: https://opam.ocaml.org
   coq.inria.fr: https://coq.inria.fr/opam/released
diff --git a/site-modules/profile/manifests/swh/deploy/worker/loader_opam.pp b/site-modules/profile/manifests/swh/deploy/worker/loader_opam.pp
--- a/site-modules/profile/manifests/swh/deploy/worker/loader_opam.pp
+++ b/site-modules/profile/manifests/swh/deploy/worker/loader_opam.pp
@@ -26,35 +26,75 @@
 
   $opam_root = lookup('swh::deploy::worker::opam::root_directory')
   $opam_manage_shared_state = "opam-manage-shared-state"
+
+  $default_systemd_path = "/etc/systemd/system"
+
+  # clean up previous versions of the opam maintenance routine
+
   $opam_manage_state_script = "/usr/local/bin/${opam_manage_shared_state}.sh"
   file {$opam_manage_state_script:
-    ensure => 'file',
-    owner  => $user,
-    group  => $group,
-    mode   => '0755',
-    content => template("${template_path}/${opam_manage_shared_state}.sh.erb"),
+    ensure => 'absent',
+  }
+
+  each ( $opam_instances ) | $instance, $instance_url | {
+    $opam_manage_service_name = "${opam_manage_shared_state}-${instance}"
+    $opam_manage_service_path = "${default_systemd_path}/${$opam_manage_service_name}.service"
+    $opam_manage_shared_state_timer_name = $opam_manage_service_name
+    $opam_manage_shared_state_timer_path = "${default_systemd_path}/${opam_manage_shared_state_timer_name}.timer"
+
+    # deactivate timer
+    ::systemd::timer { "${opam_manage_shared_state_timer_name}.timer":
+      enable => false,
+      ensure => absent,
+    }
+  }
+
+  $runparts_systemd_directory = "/run/systemd/system/opam/"
+  file {$runparts_systemd_directory:
+    ensure => directory,
+    owner   => $name,
+    group   => $group,
+    mode    => '0600',
   }
 
+  $priority = 0
   each ( $opam_instances ) | $instance, $instance_url | {
-    $opam_manage_service_name = "${$opam_manage_shared_state}-${instance}"
-    $opam_manage_shared_state_timer_name = "${opam_manage_service_name}.timer"
-
-    # Templates uses variables
-    #  - $user
-    #  - $group
-    #  - $opam_root
-    #  - $opam_manage_service_name
-    #  - $command
-
-    ::systemd::timer { $opam_manage_shared_state_timer_name:
-      timer_content    => template("${template_path}/${opam_manage_shared_state}.timer.erb"),
-      service_content  => template("${template_path}/${opam_manage_shared_state}.service.erb"),
-      enable           => true,
+    $om_instance_script_name = "${priority}-${opam_manage_shared_state}-${instance}.sh"
+    $priority = $priority + 1
+    $om_instance_script_path = "${runparts_systemd_directory}/${$om_instance_script_name}.sh"
+
+    $template_script = $instance ? {
+      'opam.ocaml.org' => 'opam-manage-shared-state-default-instance.sh',
+      default          => 'opam-manage-shared-state-secondary.sh'
+    }
+
+    file {$om_instance_script_path:
+      ensure => 'file',
+      owner  => $user,
+      group  => $group,
+      mode   => '0755',
+      content => template("${template_path}/${template_script}.erb"),
       require          => [
         Package[$packages],
-        File[$opam_manage_state_script],
+        File[$runparts_systemd_directory],
       ],
     }
   }
 
+  # Templates uses variables
+  #  - $user
+  #  - $group
+  #  - $runparts_systemd_directory
+  #  - $opam_manage_service_name
+
+  ::systemd::timer { "${opam_manage_shared_state}.timer":
+    timer_content    => template("${template_path}/${opam_manage_shared_state}.timer.erb"),
+    service_content  => template("${template_path}/${opam_manage_shared_state}.service.erb"),
+    enable           => true,
+    require          => [
+      Package[$packages],
+      File[$runparts_systemd_directory],
+    ],
+  }
+
 }
diff --git a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state-default-instance.sh.erb b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state-default-instance.sh.erb
new file mode 100644
--- /dev/null
+++ b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state-default-instance.sh.erb
@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+# Managed by puppet class profile::swh::deploy::worker::loader_opam
+# Changes will be overwritten
+
+# This script is in charge of bootstraping the opam root folder with the default opam
+# repository.
+
+set -e
+
+CMD=/usr/bin/opam
+ROOT_DIR=<%= @opam_root %>
+INSTANCE=<%= @instance %>
+INSTANCE_URL=<%= @instance_url %>
+
+# Opam instance is considered the main instance so we must initialize the repository
+# if not present, otherwise we update it
+( $CMD repo --all --root $ROOT_DIR | grep $INSTANCE_URL && $CMD update --root $ROOT_DIR ) \
+    || $CMD init --reinit --bare --no-setup --root $ROOT_DIR $INSTANCE $INSTANCE_URL
diff --git a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state-secondary.sh.erb b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state-secondary.sh.erb
new file mode 100644
--- /dev/null
+++ b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state-secondary.sh.erb
@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+# Managed by puppet class profile::swh::deploy::worker::loader_opam
+# Changes will be overwritten
+
+# This script is in charge of adding (or updating) secondary opam repositories.
+# It's expected to be called after the script which bootstrap the opam root folder.
+
+set -e
+
+CMD=/usr/bin/opam
+ROOT_DIR=<%= @opam_root %>
+INSTANCE=<%= @instance %>
+INSTANCE_URL=<%= @instance_url %>
+
+# Other instances, if present should be updated. If not present, they should be added
+# to the main root_dir as extra instances
+( $CMD repo --all --root $ROOT_DIR | grep $INSTANCE_URL && $CMD update --root $ROOT_DIR ) \
+  || $CMD repository add --root $ROOT_DIR $INSTANCE $INSTANCE_URL
diff --git a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.service.erb b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.service.erb
--- a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.service.erb
+++ b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.service.erb
@@ -3,7 +3,7 @@
 # Changes will be overwritten
 
 [Unit]
-Description=Software Heritage Manage OPAM shared state (<%= @instance %>)
+Description=Software Heritage Manage OPAM shared state
 Requires=network.target
 After=network.target
 
@@ -11,7 +11,7 @@
 User=<%= @user %>
 Group=<%= @group %>
 Type=simple
-ExecStart=/usr/local/bin/opam-manage-shared-state.sh <%= @instance %> <%= @instance_url %>
+ExecStart=/usr/bin/run-parts <%= @runparts_systemd_directory %>
 
 [Install]
 WantedBy=multi-user.target
diff --git a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.sh.erb b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.sh.erb
deleted file mode 100644
--- a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.sh.erb
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/env bash
-
-# Managed by puppet class profile::swh::deploy::worker::loader_opam
-# Changes will be overwritten
-
-CMD=/usr/bin/opam
-ROOT_DIR=<%= @opam_root %>
-DEFAULT_INSTANCE="opam.ocaml.org"
-INSTANCE=$1
-INSTANCE_URL=$2
-
-if [ $INSTANCE = $DEFAULT_INSTANCE ]; then
-  # Opam instance is considered the main instance so we must initialize the repository
-  # if not present, otherwise we update it
-  ( $CMD repo --all --root $ROOT_DIR | grep $INSTANCE_URL && $CMD update --root $ROOT_DIR ) \
-      || $CMD init --reinit --bare --no-setup --root $ROOT_DIR $INSTANCE $INSTANCE_URL
-else
-  # Other instances, if present should be updated. If not present, they should be added
-  # to the main root_dir as extra instances
-  ( $CMD repo --all --root $ROOT_DIR | grep $INSTANCE_URL && $CMD update --root $ROOT_DIR ) \
-    || $CMD repository add --root $ROOT_DIR $INSTANCE $INSTANCE_URL
-fi
diff --git a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.timer.erb b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.timer.erb
--- a/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.timer.erb
+++ b/site-modules/profile/templates/swh/deploy/loader_opam/opam-manage-shared-state.timer.erb
@@ -8,4 +8,4 @@
 Unit=<%= @opam_manage_service_name %>.service
 
 [Unit]
-Description=Software Heritage Manage OPAM shared state (<%= @instance %>) timer
+Description=Software Heritage Manage OPAM shared state timer