diff --git a/conf/app.src b/conf/app.src
index b2928bb..364a9f2 100644
--- a/conf/app.src
+++ b/conf/app.src
@@ -1,6 +1,6 @@
-SOURCE_URL=https://github.com/Chocobozzz/PeerTube/releases/download/v1.0.0-beta.4/peertube-v1.0.0-beta.4.zip
-SOURCE_SUM=4d2b60e978c9b170c733b645440b1ea29ac8b69d85adc23c36fa58a9c9db20d6
+SOURCE_URL=https://github.com/Chocobozzz/PeerTube/releases/download/v1.0.0-beta.4/peertube-v1.0.0-beta.4.tar.xz
+SOURCE_SUM=900e91a0585814d96982c10080644a4cdc0234de9730bf553c5a1e01f75b8e85
 SOURCE_SUM_PRG=sha256sum
-SOURCE_FORMAT=zip
+SOURCE_FORMAT=tar.xz
 SOURCE_IN_SUBDIR=true
 SOURCE_FILENAME=
diff --git a/scripts/backup b/scripts/backup
index c9f1208..864f5e6 100644
--- a/scripts/backup
+++ b/scripts/backup
@@ -30,9 +30,9 @@ ynh_abort_if_errors
 
 app=$YNH_APP_INSTANCE_NAME
 
-final_path=$(ynh_app_setting_get $app final_path)
-domain=$(ynh_app_setting_get $app domain)
-db_name=$(ynh_app_setting_get $app psql_db)
+final_path=$(ynh_app_setting_get "$app" final_path)
+domain=$(ynh_app_setting_get "$app" domain)
+db_name=$(ynh_app_setting_get "$app" psql_db)
 
 #=================================================
 # STANDARD BACKUP STEPS
diff --git a/scripts/install b/scripts/install
index c5ea928..6d49eae 100644
--- a/scripts/install
+++ b/scripts/install
@@ -91,7 +91,7 @@ mkdir -p "$datadir"
 ynh_install_nodejs 8
 
 # install yarn
-wget https://github.com/yarnpkg/yarn/releases/download/v1.6.0/yarn_1.6.0_all.deb
+wget -nv https://github.com/yarnpkg/yarn/releases/download/v1.6.0/yarn_1.6.0_all.deb
 echo "96866d835da94a1f01a616f3d637c9100e826f65cb38a65e5d96ccf01ff6d692  yarn_1.6.0_all.deb" | sha256sum -c || ynh_die
 dpkg -i yarn_1.6.0_all.deb
 
@@ -100,7 +100,7 @@ echo "deb http://httpredir.debian.org/debian jessie-backports main" | tee /etc/a
 ynh_package_update
 
 # install postgresql, ffmpeg, redis
-ynh_install_app_dependencies postgresql-9.4 ffmpeg redis-server redis-tools mailutils
+ynh_install_app_dependencies postgresql ffmpeg redis-server redis-tools mailutils
 
 #=================================================
 # DATABASE SETUP
@@ -114,7 +114,7 @@ ynh_app_setting_set "$app" psqlpwd "$db_pwd"
 ynh_psql_test_if_first_run
 ynh_psql_create_user "$app" "$db_pwd"
 ynh_psql_execute_as_root \
-"CREATE DATABASE $db_name ENCODING 'UTF8' LC_COLLATE='C' LC_CTYPE='C' template=template0 OWNER "$app";"
+"CREATE DATABASE $db_name ENCODING 'UTF8' LC_COLLATE='C' LC_CTYPE='C' template=template0 OWNER $app;"
 
 #=================================================
 # CREATE DEDICATED USER
@@ -130,9 +130,18 @@ ynh_system_user_create "$app"
 ynh_app_setting_set "$app" final_path "$final_path"
 # Download, check integrity, uncompress and patch the source from app.src
 ynh_setup_source "$final_path"
+
+#=================================================
+# BUILD YARN DEPENDENCIES
+#=================================================
+
 cp ../conf/production.yaml "$final_path/config/production.yaml"
 touch "$final_path/config/local-production.json"
-(cd "$final_path" && yarn install --production --pure-lockfile)
+
+(
+	cd "$final_path"
+	yarn install --production --pure-lockfile --silent --cache-folder /var/cache/yarn/
+)
 
 #=================================================
 # NGINX CONFIGURATION
@@ -144,7 +153,7 @@ ynh_add_nginx_config
 
 
 # Set right permissions for curl install
-chown -R "$app":"app" "$datadir"
+chown -R "$app":"$app" "$datadir"
 
 # Reload Nginx
 systemctl reload nginx
@@ -153,12 +162,12 @@ systemctl reload nginx
 # MODIFY A CONFIG FILE
 #=================================================
 
-ynh_replace_string "__domain__" "$domain" "$final_path/config/production.yaml"
-ynh_replace_string "__db_name__" "$app" "$final_path/config/production.yaml"
-ynh_replace_string "__app__" "$app" "$final_path/config/production.yaml"
-ynh_replace_string "__db_pwd__" "$db_pwd" "$final_path/config/production.yaml"
-ynh_replace_string "__email__" "$admin_email" "$final_path/config/production.yaml"
-ynh_replace_string "__PORT__" "$port" "$final_path/config/production.yaml"
+ynh_replace_string "__domain__"  "$domain"      "$final_path/config/production.yaml"
+ynh_replace_string "__db_name__" "$app"         "$final_path/config/production.yaml"
+ynh_replace_string "__app__"     "$app"         "$final_path/config/production.yaml"
+ynh_replace_string "__db_pwd__"  "$db_pwd"      "$final_path/config/production.yaml"
+ynh_replace_string "__email__"   "$admin_email" "$final_path/config/production.yaml"
+ynh_replace_string "__PORT__"    "$port"        "$final_path/config/production.yaml"
 
 
 #=================================================
@@ -206,7 +215,11 @@ systemctl start "$app"
 #=================================================
 
 # we need to wait for the service to init peertube's database
-(cd "/var/www/$app" && sleep 15 && exec /bin/sh -c "echo $admin_pass | NODE_CONFIG_DIR=/var/www/$app/config NODE_ENV=production PATH=/opt/node_n/bin:$PATH npm run reset-password -- -u root")
+(
+	cd "$final_path"
+	sleep 15
+	echo $admin_pass | NODE_CONFIG_DIR="$final_path/config" NODE_ENV=production PATH="/opt/node_n/bin:$PATH" npm run reset-password -- -u root
+)
 
 # Give permisiion to the final_path
 chown -R "$app":"$app" "$final_path" "$datadir"
@@ -223,9 +236,9 @@ systemctl reload nginx
 
 message="PeerTube was successfully installed :)
 
-Please open "https://$domain$path_url"
+Please open 'https://$domain$path_url'
 
-Here is the admin password: "$admin_pass"
+Here is the admin password: '$admin_pass'
 
 If you facing an issue or want to improve this app, please open a new issue in this project: https://github.com/YunoHost-Apps/peertube_ynh"
 
diff --git a/scripts/psql.sh b/scripts/psql.sh
index 0b15689..64fa8d9 100644
--- a/scripts/psql.sh
+++ b/scripts/psql.sh
@@ -7,6 +7,11 @@
 # Point of contact : Jean-Baptiste Holcroft <jean-baptiste@holcroft.fr>
 #=================================================
 
+# Create a master password and set up global settings
+# Please always call this script in install and restore scripts
+#
+# usage: ynh_psql_test_if_first_run
+
 ynh_psql_test_if_first_run() {
 	if [ -f /etc/yunohost/psql ];
 	then
@@ -27,8 +32,12 @@ ynh_psql_test_if_first_run() {
 		fi
 
 		systemctl start postgresql
-                su --command="psql -c\"ALTER user postgres WITH PASSWORD '${pgsql}'\"" postgres
-		# we can't use peer since YunoHost create users with nologin
+		sudo --login --user=postgres psql -c"ALTER user postgres WITH PASSWORD '$pgsql'" postgres
+
+		# force all user to connect to local database using passwords
+		# https://www.postgresql.org/docs/current/static/auth-pg-hba-conf.html#EXAMPLE-PG-HBA.CONF
+		# Note: we can't use peer since YunoHost create users with nologin
+		#  See: https://github.com/YunoHost/yunohost/blob/unstable/data/helpers.d/user
 		sed -i '/local\s*all\s*all\s*peer/i \
 		local all all password' "$pg_hba"
 		systemctl enable postgresql
@@ -49,7 +58,7 @@ ynh_psql_connect_as() {
 	user="$1"
 	pwd="$2"
 	db="$3"
-	su --command="PGUSER=\"${user}\" PGPASSWORD=\"${pwd}\" psql \"${db}\"" postgres
+	sudo --login --user=postgres PGUSER="$user" PGPASSWORD="$pwd" psql "$db"
 }
 
 # # Execute a command as root user
@@ -59,7 +68,7 @@ ynh_psql_connect_as() {
 # | arg: db - the database to connect to
 ynh_psql_execute_as_root () {
 	sql="$1"
-	su --command="psql" postgres <<< "$sql"
+	sudo --login --user=postgres psql <<< "$sql"
 }
 
 # Execute a command from a file as root user
@@ -70,7 +79,7 @@ ynh_psql_execute_as_root () {
 ynh_psql_execute_file_as_root() {
 	file="$1"
 	db="$2"
-	su -c "psql $db" postgres < "$file"
+	sudo --login --user=postgres psql "$db" < "$file"
 }
 
 # Create a database, an user and its password. Then store the password in the app's config
@@ -84,7 +93,6 @@ ynh_psql_execute_file_as_root() {
 # | arg: pwd - Password of the database. If not given, a password will be generated
 ynh_psql_setup_db () {
 	db_user="$1"
-	app="$1"
 	db_name="$2"
 	new_db_pwd=$(ynh_string_random)	# Generate a random password
 	# If $3 is not given, use new_db_pwd instead for db_pwd.
@@ -93,7 +101,7 @@ ynh_psql_setup_db () {
 	ynh_app_setting_set "$app" psqlpwd "$db_pwd"	# Store the password in the app's config
 }
 
-# Create a database and grant optionnaly privilegies to a user
+# Create a database and grant privilegies to a user
 #
 # usage: ynh_psql_create_db db [user [pwd]]
 # | arg: db - the database name to create
@@ -104,7 +112,7 @@ ynh_psql_create_db() {
 	user="$2"
 	pwd="$3"
 	ynh_psql_create_user "$user" "$pwd"
-	su --command="createdb --owner=\"${user}\" \"${db}\"" postgres
+	sudo --login --user=postgres createdb --owner="$user" "$db"
 }
 
 # Drop a database
@@ -115,8 +123,8 @@ ynh_psql_create_db() {
 ynh_psql_remove_db() {
 	db="$1"
 	user="$2"
-	su --command="dropdb \"${db}\"" postgres
-	ynh_psql_drop_user "${user}"
+	sudo --login --user=postgres dropdb "$db"
+	ynh_psql_drop_user "$user"
 }
 
 # Dump a database
@@ -128,7 +136,7 @@ ynh_psql_remove_db() {
 # | ret: the psqldump output
 ynh_psql_dump_db() {
 	db="$1"
-	su --command="pg_dump \"${db}\"" postgres
+	sudo --login --user=postgres pg_dump "$db"
 }
 
 
@@ -139,7 +147,7 @@ ynh_psql_dump_db() {
 ynh_psql_create_user() {
 	user="$1"
 	pwd="$2"
-        su --command="psql -c\"CREATE USER ${user} WITH PASSWORD '${pwd}'\"" postgres
+        sudo --login --user=postgres psql -c"CREATE USER $user WITH PASSWORD '$pwd'" postgres
 }
 
 # Drop a user
@@ -148,5 +156,5 @@ ynh_psql_create_user() {
 # | arg: user - the user name to drop
 ynh_psql_drop_user() {
 	user="$1"
-	su --command="dropuser \"${user}\"" postgres
-}
+	sudo --login --user=postgres dropuser "$user"
+}
\ No newline at end of file
diff --git a/scripts/remove b/scripts/remove
index 7224c83..b940a43 100644
--- a/scripts/remove
+++ b/scripts/remove
@@ -1,4 +1,3 @@
-
 #!/bin/bash
 
 #=================================================
diff --git a/scripts/restore b/scripts/restore
index 738c34a..999aebd 100644
--- a/scripts/restore
+++ b/scripts/restore
@@ -81,7 +81,7 @@ ynh_system_user_create "$app"
 
 # Set right permissions 
 datadir="/home/yunohost.app/${app}/storage"
-chown -R "$app":"app" "$datadir"
+chown -R "$app":"$app" "$datadir"
 
 #=================================================
 # SPECIFIC RESTORATION
@@ -94,16 +94,16 @@ chown -R "$app":"app" "$datadir"
 # install nodejs
 ynh_install_nodejs 8
 
-wget https://github.com/yarnpkg/yarn/releases/download/v1.5.1/yarn_1.5.1_all.deb
-echo "a4770cd8dcb13dc9a9218940dbd24b510ddf5eec78adb4e0da9ef3760b55a76e yarn_1.5.1_all.deb" | sha256sum -c || ynh_die
-dpkg -i yarn_1.5.1_all.deb
+wget -nv https://github.com/yarnpkg/yarn/releases/download/v1.6.0/yarn_1.6.0_all.deb
+echo "96866d835da94a1f01a616f3d637c9100e826f65cb38a65e5d96ccf01ff6d692  yarn_1.6.0_all.deb" | sha256sum -c || ynh_die
+dpkg -i yarn_1.6.0_all.deb
 
 # add backports (required to install ffmpeg)
 echo "deb http://httpredir.debian.org/debian jessie-backports main" | tee /etc/apt/sources.list.d/jessie-backports.list
 ynh_package_update
 
 # Define and install dependencies
-ynh_install_app_dependencies postgresql-9.4 ffmpeg redis-server redis-tools mailutils
+ynh_install_app_dependencies postgresql ffmpeg redis-server redis-tools mailutils
 
 #=================================================
 # RESTORE THE PostgreSQL DATABASE
@@ -130,10 +130,13 @@ ynh_restore_file "/etc/logrotate.d/$app"
 # RESTORE THE LOGROTATE CONFIGURATION
 #=================================================
 
-(cd "$final_path" && yarn install --production --pure-lockfile)
+(
+	cd "$final_path"
+	yarn install --production --pure-lockfile --silent --cache-folder /var/cache/yarn/
+)
 
 # Set right permissions for curl install
-chown -R "$app":"app" "$datadir"
+chown -R "$app":"$app" "$datadir"
 
 #=================================================
 # GENERIC FINALIZATION
diff --git a/scripts/upgrade b/scripts/upgrade
index 96d5149..2e46b73 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -20,7 +20,6 @@ domain=$(ynh_app_setting_get "$app" domain)
 path_url="/"
 is_public=$(ynh_app_setting_get "$app" is_public)
 admin_email=$(ynh_app_setting_get "$app" admin_email)
-admin_pass=$(ynh_app_setting_get "$app" admin_pass)
 final_path=$(ynh_app_setting_get "$app" final_path)
 port=$(ynh_app_setting_get "$app" port)
 db_name=$(ynh_app_setting_get "$app" psql_db)
@@ -86,16 +85,16 @@ ynh_system_user_create "$app"
 ynh_install_nodejs 8
 
 # install yarn
-wget https://github.com/yarnpkg/yarn/releases/download/v1.5.1/yarn_1.5.1_all.deb
-echo "a4770cd8dcb13dc9a9218940dbd24b510ddf5eec78adb4e0da9ef3760b55a76e yarn_1.5.1_all.deb" | sha256sum -c || ynh_die
-dpkg -i yarn_1.5.1_all.deb
+wget -nv https://github.com/yarnpkg/yarn/releases/download/v1.6.0/yarn_1.6.0_all.deb
+echo "96866d835da94a1f01a616f3d637c9100e826f65cb38a65e5d96ccf01ff6d692  yarn_1.6.0_all.deb" | sha256sum -c || ynh_die
+dpkg -i yarn_1.6.0_all.deb
 
 # add backports (required to install ffmpeg)
 echo "deb http://httpredir.debian.org/debian jessie-backports main" | tee /etc/apt/sources.list.d/jessie-backports.list
 ynh_package_update
 
 # install postgresql, ffmpeg, redis
-ynh_install_app_dependencies postgresql-9.4 ffmpeg redis-server redis-tools mailutils
+ynh_install_app_dependencies postgresql ffmpeg redis-server redis-tools mailutils
 
 #=================================================
 # CHECK THE PATH
@@ -104,6 +103,10 @@ ynh_install_app_dependencies postgresql-9.4 ffmpeg redis-server redis-tools mail
 # Normalize the URL path syntax
 path_url=$(ynh_normalize_url_path "$path_url")
 
+#=================================================
+# DOWNLOAD, CHECK AND UNPACK PEERTUBE SOURCE
+#=================================================
+
 # Download, check integrity, uncompress and patch the source from app.src
 ynh_setup_source "$final_path"
 cp ../conf/production.yaml "$final_path/config/production.yaml"
@@ -113,7 +116,11 @@ cp -a  "$tmpdir/local-production.json" "$final_path/config/local-production.json
 
 # Remove the tmp directory securely
 ynh_secure_remove "$tmpdir"
-(cd "$final_path" && yarn install --production --pure-lockfile)
+
+(
+	cd "$final_path"
+	yarn install --production --pure-lockfile --silent --cache-folder /var/cache/yarn/
+)
 
 
 #=================================================
@@ -133,12 +140,12 @@ systemctl reload nginx
 # MODIFY A CONFIG FILE
 #=================================================
 
-ynh_replace_string "__domain__" "$domain" "$final_path/config/production.yaml"
-ynh_replace_string "__db_name__" "$app" "$final_path/config/production.yaml"
-ynh_replace_string "__app__" "$app" "$final_path/config/production.yaml"
-ynh_replace_string "__db_pwd__" "$db_pwd" "$final_path/config/production.yaml"
-ynh_replace_string "__email__" "$admin_email" "$final_path/config/production.yaml"
-ynh_replace_string "__PORT__" "$port" "$final_path/config/production.yaml"
+ynh_replace_string "__domain__"  "$domain"      "$final_path/config/production.yaml"
+ynh_replace_string "__db_name__" "$app"         "$final_path/config/production.yaml"
+ynh_replace_string "__app__"     "$app"         "$final_path/config/production.yaml"
+ynh_replace_string "__db_pwd__"  "$db_pwd"      "$final_path/config/production.yaml"
+ynh_replace_string "__email__"   "$admin_email" "$final_path/config/production.yaml"
+ynh_replace_string "__PORT__"    "$port"        "$final_path/config/production.yaml"
 
 
 # Recalculate and store the config file checksum into the app settings
@@ -167,12 +174,12 @@ chown -R "$app":"$app" "$final_path" "$datadir"
 # SETUP SSOWAT
 #=================================================
 
-if [ $is_public -eq 0 ]
+if [ "$is_public" -eq 0 ]
 then	# Remove the public access
 	ynh_app_setting_delete "$app" skipped_uris
 fi
 # Make app public if necessary
-if [ $is_public -eq 1 ]
+if [ "$is_public" -eq 1 ]
 then
 	# unprotected_uris allows SSO credentials to be passed anyway
 	ynh_app_setting_set "$app" unprotected_uris "/"
@@ -183,6 +190,3 @@ fi
 #=================================================
 
 systemctl reload nginx
-
-
-