diff --git a/manifest.json b/manifest.json
index dfda1fa..1e5a505 100644
--- a/manifest.json
+++ b/manifest.json
@@ -15,7 +15,7 @@
         "url": "http://jserv.fr"
     },
     "requirements": {
-        "yunohost": ">= 3.4"
+        "yunohost": ">= 3.6"
     },
     "multi_instance": false,
     "services": [
diff --git a/scripts/_common.sh b/scripts/_common.sh
index 9a64378..66b9a90 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -11,10 +11,45 @@ export pkg_dependencies="apt-transport-https memcached openproject postgresql po
 # PERSONAL HELPERS
 #=================================================
 
+# Checks if string existin a file, or add it.
+ynh_string_in_file () {
+# Declare an array to define the options of this helper.
+	local legacy_args=msf
+	declare -Ar args_array=( [m]=match_string= [s]=string= [f]=target_file= )
+	local match_string
+	local string
+	local target_file
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	local delimit=@
+	# Escape the delimiter if it's in the string.
+  if grep "$match_string" $target_file; then
+  else
+    echo $string > 
+  fi
+}
+
 #=================================================
 # EXPERIMENTAL HELPERS
 #=================================================
 
+source ynh_add_extra_apt_repos
+
+# Execute a command as another user
+# usage: ynh_exec_as USER COMMAND [ARG ...]
+ynh_exec_as() {
+  local USER=$1
+  shift 1
+
+  if [[ $USER = $(whoami) ]]; then
+    eval "$@"
+  else
+    # use sudo twice to be root and be allowed to use another user
+    sudo sudo -u "$USER" "$@"
+  fi
+}
+
 #=================================================
 # FUTURE OFFICIAL HELPERS
 #=================================================
diff --git a/scripts/backup b/scripts/backup
index 34bb3e5..8f2e7a7 100755
--- a/scripts/backup
+++ b/scripts/backup
@@ -7,7 +7,7 @@
 #=================================================
 
 #Keep this path for calling _common.sh inside the execution's context of backup and restore scripts
-source _common.sh
+source ../settings/scripts/_common.sh
 source /usr/share/yunohost/helpers
 
 #=================================================
diff --git a/scripts/change_url b/scripts/change_url
index 2134bcb..9f1b072 100755
--- a/scripts/change_url
+++ b/scripts/change_url
@@ -29,6 +29,8 @@ ynh_script_progression --message="Loading installation settings..." --time --wei
 # Needed for helper "ynh_add_nginx_config"
 final_path=$(ynh_app_setting_get --app="$app" --key=final_path)
 export final_path
+port=$(ynh_app_setting_get --app="$app" --key=port)
+export port
 
 #=================================================
 # CHECK WHICH PARTS SHOULD BE CHANGED
diff --git a/scripts/install b/scripts/install
index c7bba51..e7e9e25 100755
--- a/scripts/install
+++ b/scripts/install
@@ -30,11 +30,6 @@ final_path="/var/www/$app"
 _homedir="/var/$app/"
 _openproject_install_dat="/etc/openproject/installer.dat"
 
-# Find a free port.
-# This will only be used:
-# - By OpenProject to fire app server listening to this port, and
-# - Nginx to proxify on this.
-port=$(ynh_find_port --port=6000)
 
 #=================================================
 # CHECK IF THE APP CAN BE INSTALLED WITH THESE ARGS
@@ -43,6 +38,12 @@ ynh_script_progression --message="Validating installation parameters..." --weigh
 
 test ! -e "$final_path" || ynh_die --message="This path already contains a folder"
 
+# Find a free port.
+# This will only be used:
+# - By OpenProject to fire app server listening to this port, and
+# - Nginx to proxify on this.
+port=$(ynh_find_port --port=6000)
+
 # Register (book) web path
 ynh_webpath_register --app="$app" --domain="$domain" --path_url="$path_url"
 
@@ -82,10 +83,10 @@ ynh_script_progression --message="Installing OpenProject & its dependencies..."
 
 # Add Openproject Key & repo
 # Var APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE to disable the STDOUT redirection warning
-wget -qO- https://dl.packager.io/srv/opf/openproject/key | sudo APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE=1 apt-key add - >/dev/null
-wget -qO /etc/apt/sources.list.d/openproject.list  https://dl.packager.io/srv/opf/openproject/stable/10/installer/debian/9.repo
+wget -qO- https://dl.packager.io/srv/opf/openproject/key | APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE=1 apt-key add - >/dev/null
+wget -qO /etc/apt/sources.list.d/openproject.list https://dl.packager.io/srv/opf/openproject/stable/10/installer/debian/9.repo
 
-ynh_install_app_dependencies "$pkg_dependencies"
+ynh_install_app_dependencies "$pkg_dependencies" >> "$YNH_STDINFO"
 
 #=================================================
 # NGINX CONFIGURATION
@@ -123,7 +124,7 @@ EOF
 ynh_store_file_checksum --file="$_openproject_install_dat"
 
 
-ynh_replace_string --match_string=".*PORT=.*" --replace_string="export port=$port" --target_file="/etc/default/openproject"
+ynh_replace_string --match_string=".*PORT=.*" --replace_string="export PORT=$port" --target_file="/etc/default/openproject"
 
 #=================================================
 # CREATE A POSTGRESQL DATABASE
@@ -140,7 +141,7 @@ ynh_psql_create_db "$db_name" "$db_user" "$db_pwd"
 
 ynh_script_progression --message="Post-install of OpenProject" --weight=1
 
-openproject configure
+openproject configure >> "$YNH_STDINFO"
 
 ####=================================================
 #### SETUP APPLICATION WITH CURL
diff --git a/scripts/remove b/scripts/remove
index a5bf77e..a5007e6 100755
--- a/scripts/remove
+++ b/scripts/remove
@@ -68,6 +68,7 @@ ynh_script_progression --message="Removing app main directory..."  --weight=1
 ynh_secure_remove --file="$final_path"
 ynh_secure_remove --file="$_homedir"
 ynh_secure_remove --file="/etc/$app/"
+ynh_secure_remove --file="/etc/apt/sources.list.d/openproject.list"
 
 #=================================================
 # REMOVE NGINX CONFIGURATION
diff --git a/scripts/restore b/scripts/restore
index b69f943..6a52cee 100755
--- a/scripts/restore
+++ b/scripts/restore
@@ -7,7 +7,7 @@
 #=================================================
 
 #Keep this path for calling _common.sh inside the execution's context of backup and restore scripts
-source _common.sh
+source ../settings/scripts/_common.sh
 source /usr/share/yunohost/helpers
 ynh_abort_if_errors
 
diff --git a/scripts/ynh_add_extra_apt_repos b/scripts/ynh_add_extra_apt_repos
new file mode 100644
index 0000000..e3bc5f9
--- /dev/null
+++ b/scripts/ynh_add_extra_apt_repos
@@ -0,0 +1,88 @@
+#!/bin/bash
+
+# Helper to add a repos quickly and without problem. It create a repos.list in $etc/apt/sources.list.d/. It doesn't update the repos, so it must be used with the ynh_add_dependencies.
+# usage : ynh_add_repos nameoftherepos url
+# URL IS SOMETHING LIKE : "deb $mirrorurl $prefix(stable or jessie...) $otherprefix(main, non-free, or somting like that)"
+ynh_add_repo(){
+  local name_repos="$1"
+  local url_repos="$2"
+  echo "# $name_repos
+    ${url_repos}" 
+    > "/etc/apt/sources.list.d/$name_repos.list"
+}
+
+# Helper to pin a repos easily.
+# usage : ynh_add_pin_repo nameoftherepos nbrofthepin origin 
+# Origin is the name of the orga which set up this repos ex: Debian 
+ynh_add_pin_repo() {
+  local name_repos="$1"
+  local pin="$2"
+  local origin="$3"
+  echo "Package: *
+       Pin: release o=$origin,a=$name_repos
+       Pin-Priority: $pin" \
+    > "/etc/apt/preferences.d/$name_repos"
+}
+
+# Add in a secure way backports repo.
+# usage : ynh_add_secure_backport
+ynh_add_secure_backport() {
+   local name_repos="debian-backports"
+   local origin="Debian"
+   local lsb_version="$(ynh_get_debian_release)"
+   local url="deb https://ftp.debian.org/debian $lsb_version-backports main"
+   local pin="450"
+   ynh_add_repos $name_repos $url 
+   ynh_add_pin_repo $name_repos $origin $pin
+}
+
+# Remove a repos easily in a secure way using the ynh_secure_remove helper
+ynh_rm_secure_repos() {
+  local name_repos=$1
+  ynh_secure_remove "/etc/apt/preferences.d/$name_repos"
+  ynh_secure_remove "/etc/apt/sources.list.d/$name_repos.list"
+}
+
+# Backup the repo
+ynh_backup_repo() {
+  local name_repo=$1
+  ynh_backup "/etc/apt/preference.d/$name_repo"
+  ynh_backup "/etc/apt/sources.list.d/$name_repo.list"
+}
+
+ynh_restore_repo() {
+    local name_repo=$1
+    local custom_arch=$2
+    ynh_restore "/etc/apt/preference.d/$name_repo"
+    if [[ custom_arch -ne true ]]
+        local arch_system=$(lsb_release -c)
+        arch_system=$(echo ${arch#Codename:})
+        same_arch=$(cat $name_repo | grep $arch)
+        archs = [jessie, stretch, buster]
+        ynh_restore "/etc/apt/sources.list.d/$name_repo.list"
+        for arch in archs
+        do
+            same_arch=$(cat $name_repo | grep $arch)
+            if [[ same_arch -e arch ]]
+            then
+                echo "Everything is ok"
+            else
+                sed -i "s@$arch@$arch_system@g" "/etc/apt/sources.list.d/$name_repo.list"
+            fi 
+        done
+    else 
+        echo "Attention: vous avez choisi de personnaliser votre header"
+        ynh_restore "/etc/apt/sources.list.d/$name_repo.list"
+    fi
+}
+
+ynh_backup_all_repos() {
+    if [[ $(ls /etc/apt/preference.d/) -ne "" ]]
+    then
+        ynh_backup "/etc/apt/preference.d/*"
+    fi
+    if [[ $(ls /eyc/apt/sources.list.d/) -ne "" ]] 
+    then
+        ynh_backup "/etc/apt/sources.list.d/*"
+    fi
+}
diff --git a/test b/test
new file mode 100644
index 0000000..e69de29