diff --git a/roles/app/tasks/main.yml b/roles/app/tasks/main.yml
index e24e8cb..17898a1 100644
--- a/roles/app/tasks/main.yml
+++ b/roles/app/tasks/main.yml
@@ -1,3 +1,5 @@
+# Basic dependencies installation 
+
 - name: install app dependencies
   become: true
   apt:
@@ -20,6 +22,8 @@
   tags:
     - bootstrap
 
+# User, directories, files and symlink creation
+
 - name: should have a {{ appuser }} user
   become: true
   user:
@@ -80,29 +84,6 @@
   tags:
     - bootstrap
 
-- name: install wheel and sqlparse in virtualenv
-  become: true
-  become_user: "{{ appuser }}"
-  pip:
-    name:
-      - wheel
-      - sqlparse
-    virtualenv: "{{ virtualenv }}"
-    virtualenv_command: /usr/bin/python3 -m venv
-  tags:
-    - bootstrap
-
-- name: install requirements in virtualenv
-  become: true
-  become_user: "{{ appuser }}"
-  pip:
-    requirements: "{{ appdir }}/requirements-prod.txt"
-    virtualenv: "{{ virtualenv }}"
-    virtualenv_command: /usr/bin/python3 -m venv
-  tags:
-    - bootstrap
-    - upgrade
-
 - name: save version file
   become: true
   become_user: "{{ appuser }}"
@@ -124,26 +105,6 @@
   tags:
     - bootstrap
 
-- name: create unit files
-  template:
-    src: templates/{{ item }}.j2
-    dest: "/etc/systemd/system/{{ item }}"
-  with_items:
-    - zds.service
-    - zds.socket
-    - zds-es-index.service
-    - zds-es-index.timer
-    - zds-watchdog.service
-  tags:
-    - bootstrap
-- name: add zmarkdown unit file
-  template:
-    src: zmd.service.j2
-    dest: /etc/systemd/system/zmd.service
-  tags:
-    - bootstrap
-    - upgrade
-
 - name: create app config file
   become: true
   become_user: "{{ appuser }}"
@@ -165,6 +126,55 @@
     - bootstrap
     - upgrade
 
+- name: create webroot
+  file:
+    path: "{{ webroot }}"
+    state: directory
+  tags:
+    - bootstrap
+
+- name: create symlinks in webroot
+  file:
+    src: "{{ item.src }}"
+    dest: "{{ webroot }}/{{ item.dest }}"
+    state: link
+  with_items:
+    - src: "{{ appdir }}/errors"
+      dest: "errors"
+    - src: "{{ appdir }}/robots.txt"
+      dest: "robots.txt"
+    - src: "{{ datadir }}/media"
+      dest: "media"
+    - src: "{{ datadir }}/static"
+      dest: "static"
+  tags:
+    - bootstrap
+
+# Installation of backend, frontend and zmd dependencies
+
+- name: install wheel and sqlparse in virtualenv
+  become: true
+  become_user: "{{ appuser }}"
+  pip:
+    name:
+      - wheel
+      - sqlparse
+    virtualenv: "{{ virtualenv }}"
+    virtualenv_command: /usr/bin/python3 -m venv
+  tags:
+    - bootstrap
+
+- name: install requirements in virtualenv
+  become: true
+  become_user: "{{ appuser }}"
+  pip:
+    requirements: "{{ appdir }}/requirements-prod.txt"
+    virtualenv: "{{ virtualenv }}"
+    virtualenv_command: /usr/bin/python3 -m venv
+  tags:
+    - bootstrap
+    - upgrade
+
 - include_role:
     name: common
     tasks_from: nodejs
@@ -180,6 +190,18 @@
     - bootstrap
     - upgrade
 
+- name: install zmarkdown
+  become: true
+  become_user: zds
+  npm:
+    path: "{{ zmarkdown_dir }}"
+    production: yes
+  tags:
+    - bootstrap
+    - upgrade
+
+# Frontend building
+
 - name: build frontend
   become: true
   become_user: "{{ appuser }}"
@@ -204,39 +226,8 @@
     - bootstrap
     - upgrade
 
-- name: create webroot
-  file:
-    path: "{{ webroot }}"
-    state: directory
-  tags:
-    - bootstrap
-
-- name: create symlinks in webroot
-  file:
-    src: "{{ item.src }}"
-    dest: "{{ webroot }}/{{ item.dest }}"
-    state: link
-  with_items:
-    - src: "{{ appdir }}/errors"
-      dest: "errors"
-    - src: "{{ appdir }}/robots.txt"
-      dest: "robots.txt"
-    - src: "{{ datadir }}/media"
-      dest: "media"
-    - src: "{{ datadir }}/static"
-      dest: "static"
-  tags:
-    - bootstrap
-
-- name: install zmarkdown
-  become: true
-  become_user: zds
-  npm:
-    path: "{{ zmarkdown_dir }}"
-    production: yes
-  tags:
-    - bootstrap
-    - upgrade
+# Database migration and cache clearing
+# Start of maintenance, if needed
 
 - name: check if database migration is needed
   become: true
@@ -292,6 +283,22 @@
     - bootstrap
     - upgrade
 
+# Services and timers
+
+- name: create services and timers files
+  template:
+    src: templates/{{ item }}.j2
+    dest: "/etc/systemd/system/{{ item }}"
+  with_items:
+    - zmd.service
+    - zds.service
+    - zds.socket
+    - zds-es-index.service
+    - zds-es-index.timer
+    - zds-watchdog.service
+  tags:
+    - bootstrap
+
 - name: start services and timers
   systemd:
     state: started
@@ -299,6 +306,7 @@
     enabled: yes
     daemon_reload: yes
   with_items:
+    - zmd.service
     - zds.service
     - zds.socket
     - zds-es-index.timer
@@ -306,10 +314,13 @@
   tags:
     - bootstrap
 
-- name: reload zds
+- name: reload zmarkdown and zds
   systemd:
-    name: zds
+    name: "{{ item }}"
     state: reloaded
+  with_items:
+    - zmd
+    - zds
   tags:
     - bootstrap
     - upgrade
@@ -322,24 +333,6 @@
     - bootstrap
     - upgrade
 
-- name: start zmarkdown service
-  systemd:
-    name: zmd
-    state: started
-    enabled: yes
-    daemon_reload: true
-  tags:
-    - bootstrap
-
-- name: reload zmarkdown service
-  systemd:
-    name: zmd
-    state: reloaded
-    daemon_reload: true
-  tags:
-    - bootstrap
-    - upgrade
-
 - name: ensure that zmarkdown is running
   uri:
     url: http://localhost:27272/
@@ -350,6 +343,9 @@
   until: "'zmd is running' in this.content"
   tags:
     - bootstrap
+    - upgrade
+
+# End of maintenance, if needed
 
 - name: remove maintenance symlink
   file: