diff --git a/manifest.json b/manifest.json
index f4f32e0..0721597 100644
--- a/manifest.json
+++ b/manifest.json
@@ -15,7 +15,7 @@
         "url": "https://jocelyn.delalande.fr"
     },
     "requirements": {
-        "yunohost": ">= 2.6.3"
+        "yunohost": ">= 3.8"
     },
     "multi_instance": false,
     "services": ["nginx", "mysql", "postfix"],
diff --git a/scripts/_common.sh b/scripts/_common.sh
index ba74640..3762309 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -21,19 +21,19 @@ install_apt_dependencies() {
 }
 
 create_unix_user() {
-    sudo mkdir -p /opt/yunohost
-    sudo useradd ihatemoney -d /opt/yunohost/ihatemoney/ --create-home || ynh_die "User creation failed"
+    mkdir -p /opt/yunohost
+    useradd ihatemoney -d /opt/yunohost/ihatemoney/ --create-home || ynh_die "User creation failed"
 }
 
 create_system_dirs() {
-    sudo install -o ihatemoney -g ihatemoney -m 755 -d \
+    install -o ihatemoney -g ihatemoney -m 755 -d \
          /var/log/ihatemoney \
          /etc/ihatemoney
-    sudo mkdir -p /opt/yunohost
+    mkdir -p /opt/yunohost
 }
 
 init_virtualenv () {
-    sudo virtualenv /opt/yunohost/ihatemoney/venv --python /usr/bin/python3
+    virtualenv /opt/yunohost/ihatemoney/venv --python /usr/bin/python3
 
     # PyMySQL → cryptography → setuptools>=18.5
     # Required on Jessie, Stretch has setuptools>=18.5
@@ -42,7 +42,7 @@ init_virtualenv () {
 
 pip_install () {
     # Werkzeug stuff is workaround https://github.com/spiral-project/ihatemoney/issues/540
-    sudo /opt/yunohost/ihatemoney/venv/bin/pip install --upgrade \
+    /opt/yunohost/ihatemoney/venv/bin/pip install --upgrade \
      'gunicorn>=19.3.0' \
      'PyMySQL>=0.9,<0.10' \
      'ihatemoney>=4,<5' \
@@ -55,16 +55,15 @@ configure_nginx () {
     local path=$2
     local python_version="$(readlink /usr/bin/python3|sed s/.*python//)"
 
-
-    sed -i "s@PATHTOCHANGE@$path@g" ../conf/nginx.conf
-    sed -i "s@PYTHON_VERSION@$python_version@g" ../conf/nginx.conf
+    ynh_replace_string "PATHTOCHANGE"   "$path"           ../conf/nginx.conf
+    ynh_replace_string "PYTHON_VERSION" "$python_version" ../conf/nginx.conf
     # Fix double-slash for domain-root install
-    sed -i "s@location //@location /@" ../conf/nginx.conf
-    sudo install -o root -g root -m644 \
+    ynh_replace_string "location //"    "location /"      ../conf/nginx.conf
+    install -o root -g root -m644 \
          ../conf/nginx.conf /etc/nginx/conf.d/$domain.d/ihatemoney.conf
 }
 
 configure_supervisor () {
-    sudo install -o root -g root -m 644 \
+    install -o root -g root -m 644 \
          ../conf/supervisord.conf /etc/supervisor/conf.d/ihatemoney.conf
 }
diff --git a/scripts/backup b/scripts/backup
index 9749d13..6387aec 100644
--- a/scripts/backup
+++ b/scripts/backup
@@ -1,6 +1,7 @@
 #!/bin/bash
 
 # Source YunoHost helpers
+source ../settings/scripts/_common.sh
 source /usr/share/yunohost/helpers
 
 ynh_abort_if_errors
@@ -19,15 +20,6 @@ domain=$(ynh_app_setting_get "$app" domain)
 path=$(ynh_app_setting_get "$app" path)
 dbpass=$(ynh_app_setting_get "$app" mysqlpwd)
 
-# Source local utils
-if [ ! -e _common.sh ]; then
-	# Fetch the local helpers files, because unavail to restore script
-	sudo cp ../settings/scripts/_common.sh ./_common.sh
-	sudo chmod a+rx _common.sh
-fi
-
-source _common.sh
-
 # Backup conf files
 mkdir ./conf
 ynh_backup "$nginx_conf_path" "conf/nginx.conf"
diff --git a/scripts/install b/scripts/install
index b6f8061..8c1202c 100755
--- a/scripts/install
+++ b/scripts/install
@@ -1,6 +1,7 @@
 #!/bin/bash
 
 # Source YunoHost helpers
+source _common.sh
 source /usr/share/yunohost/helpers
 
 # Retrieve arguments
@@ -9,19 +10,13 @@ path=$YNH_APP_ARG_PATH
 is_public=$YNH_APP_ARG_IS_PUBLIC
 app=ihatemoney
 
-# Source local utils
-source _common.sh
-
-path=$(ynh_normalize_url_path $path)
-
 # Database settings
 db_pwd=$(ynh_string_random)
 db_name=$app
 db_user=$app
 
 # Constant arguments
-db_user=ihatemoney
-secret_key=`openssl rand -base64 32`
+secret_key=$(ynh_string_random --length 32)
 mails_sender="no-reply@${domain}"
 
 
@@ -31,11 +26,10 @@ ynh_webpath_register $app $domain $path
 
 # Configure database
 ynh_mysql_create_db "$db_name" "$db_user" "$db_pwd"
-ynh_app_setting_set $app mysqlpwd $db_pwd
 
 # Save app settings
-ynh_app_setting_set $app domain $domain
-ynh_app_setting_set $app is_public "$is_public"
+ynh_app_setting_set "$app" mysqlpwd "$db_pwd"
+ynh_app_setting_set "$app" is_public "$is_public"
 
 install_apt_dependencies
 
@@ -48,7 +42,7 @@ pip_install
 create_system_dirs
 
 # Configure gunicorn
-sudo install -o ihatemoney -g ihatemoney -m 644 \
+install -o ihatemoney -g ihatemoney -m 644 \
      ../conf/gunicorn.conf.py /etc/ihatemoney/gunicorn.conf.py
 
 # Configure supervisor
@@ -56,16 +50,16 @@ configure_supervisor
 # In case it was already installed before,
 # so that it picks /etc/supervisor/conf.d/ihatemoney.conf:
 supervisorctl update
-sudo yunohost service add supervisor
+yunohost service add supervisor
 
 # Configure ihatemoney
-sed -i "s@MY_SECRET_KEY@$secret_key@" ../conf/ihatemoney.cfg
-sed -i "s/MY_EMAIL/$mails_sender/" ../conf/ihatemoney.cfg
-sed -i "s@MY_MYSQL_PW@$db_pwd@" ../conf/ihatemoney.cfg
-sed -i "s@MY_PATH@$path@" ../conf/ihatemoney.cfg
+ynh_replace_string "MY_SECRET_KEY" "$secret_key"   ../conf/ihatemoney.cfg
+ynh_replace_string "MY_EMAIL"      "$mails_sender" ../conf/ihatemoney.cfg
+ynh_replace_string "MY_MYSQL_PW"   "$db_pwd"       ../conf/ihatemoney.cfg
+ynh_replace_string "MY_PATH"       "$path"         ../conf/ihatemoney.cfg
 # Remove the conf directive if served at root
 sed -i "/APPLICATION_ROOT='\/'/d" ../conf/ihatemoney.cfg
-sudo install -o ihatemoney -g ihatemoney -m 640 \
+install -o ihatemoney -g ihatemoney -m 640 \
      ../conf/ihatemoney.cfg /etc/ihatemoney/ihatemoney.cfg
 
 # If app is public, add url to SSOWat conf as skipped_uris
@@ -78,10 +72,7 @@ fi
 configure_nginx "$domain" "$path"
 
 # Start backend
-sudo systemctl start supervisor
-
-# Reconfigure sso
-sudo yunohost app ssowatconf
+systemctl start supervisor
 
 # Wait that gunicorn is ready to consider the install finished, that is to
 # avoid HTTP 502 right after installation
@@ -92,6 +83,6 @@ do
 done
 
 # If socket not ready after 2 minutes waiting, ihatemoney will not work.
-test -S /tmp/budget.gunicorn.sock || exit_properly
+test -S /tmp/budget.gunicorn.sock || ynh_die
 
-sudo systemctl reload nginx
+systemctl reload nginx
diff --git a/scripts/remove b/scripts/remove
index be63595..f908c51 100755
--- a/scripts/remove
+++ b/scripts/remove
@@ -11,27 +11,24 @@ app=ihatemoney
 domain=$(ynh_app_setting_get $app domain)
 db_user=$app
 db_name=$app
-root_pwd=$(sudo cat /etc/yunohost/mysql)
 
 # Stop service
-sudo supervisorctl stop budget
+supervisorctl stop budget
 
 # Drop database
 ynh_mysql_drop_db $db_name
 ynh_mysql_drop_user $db_user
 
 # Remove src and venv
-sudo rm -rf /opt/yunohost/ihatemoney/
+ynh_secure_remove /opt/yunohost/ihatemoney/
 
 # Remove settings
-sudo rm -rf /etc/ihatemoney
-sudo rm /etc/supervisor/conf.d/ihatemoney.conf
-sudo rm /etc/nginx/conf.d/$domain.d/ihatemoney.conf
+ynh_secure_remove /etc/ihatemoney
+ynh_secure_remove /etc/supervisor/conf.d/ihatemoney.conf
+ynh_remove_nginx_config
 
 # Restart services
-sudo systemctl force-reload supervisor
-sudo systemctl reload nginx
-sudo yunohost app ssowatconf
+systemctl force-reload supervisor
 
 # Delete user
-sudo userdel ihatemoney
+userdel ihatemoney
diff --git a/scripts/restore b/scripts/restore
index 5852c6c..7bf2e3e 100644
--- a/scripts/restore
+++ b/scripts/restore
@@ -1,8 +1,11 @@
 #!/bin/bash
 
 # Source app helpers
+source ../settings/scripts/_common.sh
 source /usr/share/yunohost/helpers
 
+ynh_abort_if_errors
+
 # Get multi-instances specific variables
 app=$YNH_APP_INSTANCE_NAME
 
@@ -16,17 +19,6 @@ path=$(ynh_app_setting_get "$app" path)
 dbpass=$(ynh_app_setting_get "$app" mysqlpwd)
 
 
-# Source local utils
-if [ ! -e _common.sh ]; then
-	# Fetch the local helpers files, because unavail to restore script
-	sudo cp ../settings/scripts/_common.sh ./_common.sh
-	sudo chmod a+rx _common.sh
-fi
-
-source _common.sh
-
-ynh_abort_if_errors
-
 test -d $INSTALL_DIR && ynh_die \
 "The destination directory '$INSTALL_DIR' already exists.\
  You should safely delete it before restoring this app."
@@ -57,6 +49,6 @@ ynh_mysql_create_db "$dbname" "$dbuser" "$dbpass"
 ynh_mysql_connect_as "$dbuser" "$dbpass" "$dbname" < ./db.sql
 
 # Reload
-sudo systemctl reload nginx
-sudo systemctl restart supervisor
-sudo supervisorctl restart budget
+systemctl reload nginx
+systemctl restart supervisor
+supervisorctl restart budget
diff --git a/scripts/upgrade b/scripts/upgrade
index 71de201..5bfd8b1 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -21,7 +21,7 @@ source _common.sh
 ynh_clean_setup () {
     if [ -e /opt/yunohost/ihatemoney/venv-old ]
     then
-        sudo mv /opt/yunohost/ihatemoney/venv{-old,}
+        mv /opt/yunohost/ihatemoney/venv{-old,}
     fi
 }
 
@@ -52,13 +52,13 @@ if [[ "$VENV_PY_VERSION" == 2.7 ]]
 then
     install_apt_dependencies
     # Trash py2 venv
-    sudo mv ${INSTALL_DIR}/venv ${INSTALL_DIR}/venv-old
+    mv ${INSTALL_DIR}/venv ${INSTALL_DIR}/venv-old
     init_virtualenv
 
     # Clears all cookie-sessions, because py2 & py3 sessions are incompatible
     # Relates https://github.com/lepture/flask-wtf/issues/279 (fix unreleased)
-    new_secret_key=`openssl rand -base64 32`
-    sudo sed -i "s/SECRET_KEY = \".*\"/SECRET_KEY = \"${new_secret_key}\"/g" /etc/ihatemoney/ihatemoney.cfg
+    new_secret_key=$(ynh_string_random 32)
+    ynh_replace_string "SECRET_KEY = \".*\"" "SECRET_KEY = \"${new_secret_key}\"" /etc/ihatemoney/ihatemoney.cfg
 fi
 
 
@@ -68,7 +68,7 @@ fi
 # Useful for  Py 3.4 → 3.5, Jessie → Stretch, ynh 2.x → 3.x
 if [[ "$VENV_PY_VERSION" != '2.7' ]] && [[ "$VENV_PY_VERSION" != "$SYSTEM_PY_VERSION" ]]
 then
-    sudo mv ${INSTALL_DIR}/venv ${INSTALL_DIR}/venv-old
+    mv ${INSTALL_DIR}/venv ${INSTALL_DIR}/venv-old
     init_virtualenv
 
     # the static path changed
@@ -88,13 +88,13 @@ pip_install
 
 
 # Python-MySQL is no longer maintained and does not support Py3
-sudo sed -i "s@'mysql://@'mysql+pymysql://@g" ${ihatemoney_conf_path}
+ynh_replace_string "'mysql://" "'mysql+pymysql://" ${ihatemoney_conf_path}
 
 
 
 # MIGRATION: Remove old code (from pre-2.x versions, not using pip)
 
-sudo rm -rf ${INSTALL_DIR}/src
+ynh_secure_remove ${INSTALL_DIR}/src
 
 
 
@@ -115,9 +115,9 @@ fi
 
 if [ -e /etc/ihatemoney/settings.py ]; then
     # Strip out the no longer used part of the settings
-    sudo python2 -c "d = open('/etc/ihatemoney/settings.py').read().replace('try:\n    from settings import *\nexcept ImportError:\n    pass\n', ''); open('/etc/ihatemoney/settings.py', 'w').write(d)"
+    python2 -c "d = open('/etc/ihatemoney/settings.py').read().replace('try:\n    from settings import *\nexcept ImportError:\n    pass\n', ''); open('/etc/ihatemoney/settings.py', 'w').write(d)"
     # Rename
-    sudo mv /etc/ihatemoney/settings.py ${ihatemoney_conf_path}
+    mv /etc/ihatemoney/settings.py ${ihatemoney_conf_path}
 fi
 
 
@@ -125,17 +125,17 @@ fi
 # MIGRATION: Remove no longer used symlink
 
 # (ihatemoney now read its conf by default from /etc/ihatemoney/ihatemoney.cfg)
-sudo rm -f ${INSTALL_DIR}/src/budget/settings.py
+ynh_secure_remove ${INSTALL_DIR}/src/budget/settings.py
 
 
 
 #----------------------------FINALIZATION-----------------------
 
 # Everything went ok ? Let's keep this new venv.
-sudo rm -rf ${INSTALL_DIR}/venv-old
+ynh_secure_remove ${INSTALL_DIR}/venv-old
 
 # Restart backend
-sudo supervisorctl restart budget
+supervisorctl restart budget
 
 # Reload nginx conf
-sudo systemctl reload nginx
+systemctl reload nginx