diff --git a/data/helpers.d/apt b/data/helpers.d/apt
index a1eb6f470..9d2c2b64c 100644
--- a/data/helpers.d/apt
+++ b/data/helpers.d/apt
@@ -27,7 +27,7 @@ ynh_wait_dpkg_free() {
             while read dpkg_file <&9
             do
                 # Check if the name of this file contains only numbers.
-                if echo "$dpkg_file" | grep -Pq "^[[:digit:]]+$"
+                if echo "$dpkg_file" | grep --perl-regexp --quiet "^[[:digit:]]+$"
                 then
                     # If so, that a remaining of dpkg.
                     ynh_print_err "E: dpkg was interrupted, you must manually run 'sudo dpkg --configure -a' to correct the problem."
@@ -57,8 +57,8 @@ ynh_package_is_installed() {
     ynh_handle_getopts_args "$@"
 
     ynh_wait_dpkg_free
-    dpkg-query -W -f '${Status}' "$package" 2>/dev/null \
-        | grep -c "ok installed" &>/dev/null
+    dpkg-query --show --showformat='${Status}' "$package" 2>/dev/null \
+        | grep --count "ok installed" &>/dev/null
 }
 
 # Get the version of an installed package
@@ -80,7 +80,7 @@ ynh_package_version() {
 
     if ynh_package_is_installed "$package"
     then
-        dpkg-query -W -f '${Version}' "$package" 2>/dev/null
+        dpkg-query --show --showformat='${Version}' "$package" 2>/dev/null
     else
         echo ''
     fi
@@ -95,7 +95,7 @@ ynh_package_version() {
 # Requires YunoHost version 2.4.0.3 or higher.
 ynh_apt() {
     ynh_wait_dpkg_free
-    LC_ALL=C DEBIAN_FRONTEND=noninteractive apt-get -y $@
+    LC_ALL=C DEBIAN_FRONTEND=noninteractive apt-get --assume-yes $@
 }
 
 # Update package index files
@@ -114,8 +114,8 @@ ynh_package_update() {
 #
 # Requires YunoHost version 2.2.4 or higher.
 ynh_package_install() {
-    ynh_apt --no-remove -o Dpkg::Options::=--force-confdef \
-        -o Dpkg::Options::=--force-confold install $@
+    ynh_apt --no-remove --option Dpkg::Options::=--force-confdef \
+        --option Dpkg::Options::=--force-confold install $@
 }
 
 # Remove package(s)
@@ -164,8 +164,8 @@ ynh_package_install_from_equivs () {
     local controlfile=$1
 
     # retrieve package information
-    local pkgname=$(grep '^Package: ' $controlfile | cut -d' ' -f 2)	# Retrieve the name of the debian package
-    local pkgversion=$(grep '^Version: ' $controlfile | cut -d' ' -f 2)	# And its version number
+    local pkgname=$(grep '^Package: ' $controlfile | cut --delimiter=' ' --fields=2)	# Retrieve the name of the debian package
+    local pkgversion=$(grep '^Version: ' $controlfile | cut --delimiter=' ' --fields=2)	# And its version number
     [[ -z "$pkgname" || -z "$pkgversion" ]] \
         && ynh_die --message="Invalid control file"	# Check if this 2 variables aren't empty.
 
@@ -173,7 +173,7 @@ ynh_package_install_from_equivs () {
     ynh_package_update
 
     # Build and install the package
-    local TMPDIR=$(mktemp -d)
+    local TMPDIR=$(mktemp --directory)
 
     # Force the compatibility level at 10, levels below are deprecated 
     echo 10 > /usr/share/equivs/template/debian/compat
@@ -186,21 +186,21 @@ ynh_package_install_from_equivs () {
     cp "$controlfile" "${TMPDIR}/control"
     (cd "$TMPDIR"
     LC_ALL=C equivs-build ./control 1> /dev/null
-    dpkg --force-depends -i "./${pkgname}_${pkgversion}_all.deb" 2>&1)
+    dpkg --force-depends --install "./${pkgname}_${pkgversion}_all.deb" 2>&1)
     # If install fails we use "apt-get check" to try to debug and diagnose possible unmet dependencies
     # Note the use of { } which allows to group commands without starting a subshell (otherwise the ynh_die wouldn't exit the current shell). 
     # Be careful with the syntax : the semicolon + space at the end is important!
 
-    ynh_package_install -f || \
+    ynh_package_install --fix-broken || \
         { # If the installation failed
         # Get the list of dependencies from the deb
         local dependencies="$(dpkg --info "$TMPDIR/${pkgname}_${pkgversion}_all.deb" | grep Depends | \
             sed 's/^ Depends: //' | sed 's/,//g')"
         # Fake an install of those dependencies to see the errors
         # The sed command here is, Print only from '--fix-broken' to the end.
-        ynh_package_install $dependencies --dry-run | sed -n '/--fix-broken/,$p' >&2
+        ynh_package_install $dependencies --dry-run | sed --quiet '/--fix-broken/,$p' >&2
         ynh_die --message="Unable to install dependencies"; }
-    [[ -n "$TMPDIR" ]] && rm -rf $TMPDIR	# Remove the temp dir.
+    [[ -n "$TMPDIR" ]] && rm --recursive --force $TMPDIR	# Remove the temp dir.
 
     # check if the package is actually installed
     ynh_package_is_installed "$pkgname"
@@ -226,7 +226,7 @@ ynh_install_app_dependencies () {
         manifest_path="../settings/manifest.json"	# Into the restore script, the manifest is not at the same place
     fi
 
-    local version=$(grep '\"version\": ' "$manifest_path" | cut -d '"' -f 4)	# Retrieve the version number in the manifest file.
+    local version=$(grep '\"version\": ' "$manifest_path" | cut --delimiter='"' --fields=4)	# Retrieve the version number in the manifest file.
     if [ ${#version} -eq 0 ]; then
         version="1.0"
     fi
@@ -252,16 +252,16 @@ ynh_install_app_dependencies () {
     # https://github.com/YunoHost/issues/issues/1407
     # 
     # If we require to install php dependency
-    if echo $dependencies | grep -q 'php'
+    if echo $dependencies | grep --quiet 'php'
     then
         # And we have packages from sury installed (7.0.33-10+weirdshiftafter instead of 7.0.33-0 on debian)
-        if dpkg --list | grep "php7.0" | grep -q -v "7.0.33-0+deb9"
+        if dpkg --list | grep "php7.0" | grep --quiet --invert-match "7.0.33-0+deb9"
         then
             # And sury ain't already installed
-            if ! grep -nrq "sury" /etc/apt/sources.list*
+            if ! grep --line-number --recursive --quiet "sury" /etc/apt/sources.list*
             then
                 # Re-add sury
-                ynh_install_extra_repo --repo="https://packages.sury.org/php/ $(lsb_release -sc) main" --key="https://packages.sury.org/php/apt.gpg" --name=extra_php_version
+                ynh_install_extra_repo --repo="https://packages.sury.org/php/ $(ynh_get_debian_release) main" --key="https://packages.sury.org/php/apt.gpg" --name=extra_php_version
 
                 # Pin this sury repository to prevent sury of doing shit
                 ynh_pin_repo --package="*" --pin="origin \"packages.sury.org\"" --priority=200 --name=extra_php_version
@@ -396,7 +396,7 @@ ynh_install_extra_repo () {
     if [ $append -eq 1 ]
     then
         append="--append"
-        wget_append="tee -a"
+        wget_append="tee --append"
     else
         append=""
         wget_append="tee"
@@ -432,8 +432,8 @@ ynh_install_extra_repo () {
     # Get the public key for the repo
     if [ -n "$key" ]
     then
-        mkdir -p "/etc/apt/trusted.gpg.d"
-        wget -q "$key" -O - | gpg --dearmor | $wget_append /etc/apt/trusted.gpg.d/$name.gpg > /dev/null
+        mkdir --parents "/etc/apt/trusted.gpg.d"
+        wget --quiet "$key" --output-document=- | gpg --dearmor | $wget_append /etc/apt/trusted.gpg.d/$name.gpg > /dev/null
     fi
 
     # Update the list of package with the new repo
@@ -495,12 +495,12 @@ ynh_add_repo () {
 
     if [ $append -eq 1 ]
     then
-        append="tee -a"
+        append="tee --append"
     else
         append="tee"
     fi
 
-    mkdir -p "/etc/apt/sources.list.d"
+    mkdir --parents "/etc/apt/sources.list.d"
     # Add the new repo in sources.list.d
     echo "deb $uri $suite $component" \
         | $append "/etc/apt/sources.list.d/$name.list"
@@ -537,12 +537,12 @@ ynh_pin_repo () {
 
     if [ $append -eq 1 ]
     then
-        append="tee -a"
+        append="tee --append"
     else
         append="tee"
     fi
 
-    mkdir -p "/etc/apt/preferences.d"
+    mkdir --parents "/etc/apt/preferences.d"
     echo "Package: $package
 Pin: $pin
 Pin-Priority: $priority
diff --git a/data/helpers.d/backup b/data/helpers.d/backup
index 096804380..60e9fca94 100644
--- a/data/helpers.d/backup
+++ b/data/helpers.d/backup
@@ -144,15 +144,15 @@ ynh_backup() {
     # ==============================================================================
     # Write file to backup into backup_list
     # ==============================================================================
-    local src=$(echo "${src_path}" | sed -r 's/"/\"\"/g')
-    local dest=$(echo "${dest_path}" | sed -r 's/"/\"\"/g')
+    local src=$(echo "${src_path}" | sed --regexp-extended 's/"/\"\"/g')
+    local dest=$(echo "${dest_path}" | sed --regexp-extended 's/"/\"\"/g')
     echo "\"${src}\",\"${dest}\"" >> "${YNH_BACKUP_CSV}"
 
     # ==============================================================================
 
     # Create the parent dir of the destination path
     # It's for retro compatibility, some script consider ynh_backup creates this dir
-    mkdir -p $(dirname "$YNH_BACKUP_DIR/${dest_path}")
+    mkdir --parents $(dirname "$YNH_BACKUP_DIR/${dest_path}")
 }
 
 # Restore all files that were previously backuped in a core backup script or app backup script
@@ -166,11 +166,11 @@ ynh_restore () {
     REL_DIR="${REL_DIR%/}/"
 
     # For each destination path begining by $REL_DIR
-    cat ${YNH_BACKUP_CSV} | tr -d $'\r' | grep -ohP "^\".*\",\"$REL_DIR.*\"$" | \
+    cat ${YNH_BACKUP_CSV} | tr --delete $'\r' | grep --only-matching --no-filename --perl-regexp "^\".*\",\"$REL_DIR.*\"$" | \
     while read line
     do
-        local ORIGIN_PATH=$(echo "$line" | grep -ohP "^\"\K.*(?=\",\".*\"$)")
-        local ARCHIVE_PATH=$(echo "$line" | grep -ohP "^\".*\",\"$REL_DIR\K.*(?=\"$)")
+        local ORIGIN_PATH=$(echo "$line" | grep --only-matching --no-filename --perl-regexp "^\"\K.*(?=\",\".*\"$)")
+        local ARCHIVE_PATH=$(echo "$line" | grep --only-matching --no-filename --perl-regexp "^\".*\",\"$REL_DIR\K.*(?=\"$)")
         ynh_restore_file --origin_path="$ARCHIVE_PATH" --dest_path="$ORIGIN_PATH"
     done
 }
@@ -251,10 +251,10 @@ ynh_restore_file () {
     if [[ -e "${dest_path}" ]]
     then
         # Check if the file/dir size is less than 500 Mo
-        if [[ $(du -sb ${dest_path} | cut -d"/" -f1) -le "500000000" ]]
+        if [[ $(du --summarize --bytes ${dest_path} | cut --delimiter="/" --fields=1) -le "500000000" ]]
         then
             local backup_file="/home/yunohost.conf/backup/${dest_path}.backup.$(date '+%Y%m%d.%H%M%S')"
-            mkdir -p "$(dirname "$backup_file")"
+            mkdir --parents "$(dirname "$backup_file")"
             mv "${dest_path}" "$backup_file"    # Move the current file or directory
         else
             ynh_secure_remove --file=${dest_path}
@@ -262,17 +262,17 @@ ynh_restore_file () {
     fi
 
     # Restore origin_path into dest_path
-    mkdir -p $(dirname "$dest_path")
+    mkdir --parents $(dirname "$dest_path")
 
     # Do a copy if it's just a mounting point
-    if mountpoint -q $YNH_BACKUP_DIR
+    if mountpoint --quiet $YNH_BACKUP_DIR
     then
         if [[ -d "${archive_path}" ]]
         then
             archive_path="${archive_path}/."
-            mkdir -p "$dest_path"
+            mkdir --parents "$dest_path"
         fi
-        cp -a "$archive_path" "${dest_path}"
+        cp --archive "$archive_path" "${dest_path}"
     # Do a move if YNH_BACKUP_DIR is already a copy
     else
         mv "$archive_path" "${dest_path}"
@@ -308,7 +308,7 @@ ynh_store_file_checksum () {
     ynh_handle_getopts_args "$@"
 
     local checksum_setting_name=checksum_${file//[\/ ]/_}    # Replace all '/' and ' ' by '_'
-    ynh_app_setting_set --app=$app --key=$checksum_setting_name --value=$(md5sum "$file" | cut -d' ' -f1)
+    ynh_app_setting_set --app=$app --key=$checksum_setting_name --value=$(md5sum "$file" | cut --delimiter=' ' --fields=1)
 
     # If backup_file_checksum isn't empty, ynh_backup_if_checksum_is_different has made a backup
     if [ -n "${backup_file_checksum-}" ]
@@ -345,11 +345,11 @@ ynh_backup_if_checksum_is_different () {
     backup_file_checksum=""
     if [ -n "$checksum_value" ]
     then    # Proceed only if a value was stored into the app settings
-        if [ -e $file ] && ! echo "$checksum_value $file" | md5sum -c --status
+        if [ -e $file ] && ! echo "$checksum_value $file" | md5sum --check --status
         then    # If the checksum is now different
             backup_file_checksum="/home/yunohost.conf/backup/$file.backup.$(date '+%Y%m%d.%H%M%S')"
-            mkdir -p "$(dirname "$backup_file_checksum")"
-            cp -a "$file" "$backup_file_checksum"    # Backup the current file
+            mkdir --parents "$(dirname "$backup_file_checksum")"
+            cp --archive "$file" "$backup_file_checksum"    # Backup the current file
             ynh_print_warn "File $file has been manually modified since the installation or last upgrade. So it has been duplicated in $backup_file_checksum"
             echo "$backup_file_checksum"    # Return the name of the backup file
         fi
@@ -400,7 +400,7 @@ ynh_backup_before_upgrade () {
     if [ "$NO_BACKUP_UPGRADE" -eq 0 ]
     then
         # Check if a backup already exists with the prefix 1
-        if yunohost backup list | grep -q $app_bck-pre-upgrade1
+        if yunohost backup list | grep --quiet $app_bck-pre-upgrade1
         then
             # Prefix becomes 2 to preserve the previous backup
             backup_number=2
@@ -412,7 +412,7 @@ ynh_backup_before_upgrade () {
         if [ "$?" -eq 0 ]
         then
             # If the backup succeeded, remove the previous backup
-            if yunohost backup list | grep -q $app_bck-pre-upgrade$old_backup_number
+            if yunohost backup list | grep --quiet $app_bck-pre-upgrade$old_backup_number
             then
                 # Remove the previous backup only if it exists
                 yunohost backup delete $app_bck-pre-upgrade$old_backup_number > /dev/null
@@ -444,7 +444,7 @@ ynh_restore_upgradebackup () {
     if [ "$NO_BACKUP_UPGRADE" -eq 0 ]
     then
         # Check if an existing backup can be found before removing and restoring the application.
-        if yunohost backup list | grep -q $app_bck-pre-upgrade$backup_number
+        if yunohost backup list | grep --quiet $app_bck-pre-upgrade$backup_number
         then
             # Remove the application then restore it
             yunohost app remove $app
diff --git a/data/helpers.d/fail2ban b/data/helpers.d/fail2ban
index 438b3b355..1eef67f5c 100644
--- a/data/helpers.d/fail2ban
+++ b/data/helpers.d/fail2ban
@@ -133,7 +133,7 @@ EOF
 
     ynh_systemd_action --service_name=fail2ban --action=reload
 
-    local fail2ban_error="$(journalctl -u fail2ban | tail -n50 | grep "WARNING.*$app.*")"
+    local fail2ban_error="$(journalctl --unit=fail2ban | tail --lines=50 | grep "WARNING.*$app.*")"
     if [[ -n "$fail2ban_error" ]]
     then
         ynh_print_err --message="Fail2ban failed to load the jail for $app"
diff --git a/data/helpers.d/getopts b/data/helpers.d/getopts
index 1717ea8fc..4dfd08d9e 100644
--- a/data/helpers.d/getopts
+++ b/data/helpers.d/getopts
@@ -47,7 +47,7 @@
 # Requires YunoHost version 3.2.2 or higher.
 ynh_handle_getopts_args () {
     # Manage arguments only if there's some provided
-    set +x
+    set +o xtrace # set +x
     if [ $# -ne 0 ]
     then
         # Store arguments in an array to keep each argument separated
@@ -216,5 +216,5 @@ ynh_handle_getopts_args () {
             parse_arg "${arguments[@]}"
         fi
     fi
-    set -x
+    set -o xtrace # set -x
 }
diff --git a/data/helpers.d/logging b/data/helpers.d/logging
index 0cd25fb57..812709921 100644
--- a/data/helpers.d/logging
+++ b/data/helpers.d/logging
@@ -46,7 +46,7 @@ ynh_print_info() {
 # Requires YunoHost version 2.6.4 or higher.
 ynh_no_log() {
     local ynh_cli_log=/var/log/yunohost/yunohost-cli.log
-    cp -a ${ynh_cli_log} ${ynh_cli_log}-move
+    cp --archive ${ynh_cli_log} ${ynh_cli_log}-move
     eval $@
     local exit_code=$?
     mv ${ynh_cli_log}-move ${ynh_cli_log}
@@ -221,7 +221,7 @@ base_time=$(date +%s)
 #
 # Requires YunoHost version 3.5.0 or higher.
 ynh_script_progression () {
-    set +x
+    set +o xtrace # set +x
     # Declare an array to define the options of this helper.
     local legacy_args=mwtl
     local -A args_array=( [m]=message= [w]=weight= [t]=time [l]=last )
@@ -231,7 +231,7 @@ ynh_script_progression () {
     local last
     # Manage arguments with getopts
     ynh_handle_getopts_args "$@"
-    set +x
+    set +o xtrace # set +x
     weight=${weight:-1}
     time=${time:-0}
     last=${last:-0}
@@ -295,7 +295,7 @@ ynh_script_progression () {
     fi
 
     ynh_print_info "[$progression_bar] > ${message}${print_exec_time}"
-    set -x
+    set -o xtrace # set -x
 }
 
 # Return data to the Yunohost core for later processing
@@ -317,7 +317,7 @@ ynh_return () {
 # Requires YunoHost version 3.5.0 or higher.
 ynh_debug () {
     # Disable set xtrace for the helper itself, to not pollute the debug log
-    set +x
+    set +o xtrace # set +x
     # Declare an array to define the options of this helper.
     local legacy_args=mt
     local -A args_array=( [m]=message= [t]=trace= )
@@ -326,7 +326,7 @@ ynh_debug () {
     # Manage arguments with getopts
     ynh_handle_getopts_args "$@"
     # Redisable xtrace, ynh_handle_getopts_args set it back
-    set +x
+    set +o xtrace # set +x
     message=${message:-}
     trace=${trace:-}
 
@@ -338,7 +338,7 @@ ynh_debug () {
     if [ "$trace" == "1" ]
     then
         ynh_debug --message="Enable debugging"
-        set +x
+        set +o xtrace # set +x
         # Get the current file descriptor of xtrace
         old_bash_xtracefd=$BASH_XTRACEFD
         # Add the current file name and the line number of any command currently running while tracing.
@@ -351,14 +351,14 @@ ynh_debug () {
     if [ "$trace" == "0" ]
     then
         ynh_debug --message="Disable debugging"
-        set +x
+        set +o xtrace # set +x
         # Put xtrace back to its original fild descriptor
         BASH_XTRACEFD=$old_bash_xtracefd
         # Restore stdout
         exec 1>&1
     fi
     # Renable set xtrace
-    set -x
+    set -o xtrace # set -x
 }
 
 # Execute a command and print the result as debug
diff --git a/data/helpers.d/logrotate b/data/helpers.d/logrotate
index 3cd835eee..b9af082a6 100644
--- a/data/helpers.d/logrotate
+++ b/data/helpers.d/logrotate
@@ -55,7 +55,7 @@ ynh_use_logrotate () {
     fi
     # LEGACY CODE
 
-    local customtee="tee -a"
+    local customtee="tee --append"
     if [ "$nonappend" -eq 1 ]; then
         customtee="tee"
     fi
@@ -95,7 +95,7 @@ $logfile {
     $su_directive
 }
 EOF
-    mkdir -p $(dirname "$logfile")	# Create the log directory, if not exist
+    mkdir --parents $(dirname "$logfile")	# Create the log directory, if not exist
     cat ${app}-logrotate | $customtee /etc/logrotate.d/$app > /dev/null	# Append this config to the existing config file, or replace the whole config file (depending on $customtee)
 }
 
diff --git a/data/helpers.d/mysql b/data/helpers.d/mysql
index 52c65cc63..62edd8822 100644
--- a/data/helpers.d/mysql
+++ b/data/helpers.d/mysql
@@ -24,7 +24,7 @@ ynh_mysql_connect_as() {
     ynh_handle_getopts_args "$@"
     database="${database:-}"
 
-    mysql -u "$user" --password="$password" -B "$database"
+    mysql --user="$user" --password="$password" --batch "$database"
 }
 
 # Execute a command as root user
@@ -127,7 +127,7 @@ ynh_mysql_dump_db() {
     # Manage arguments with getopts
     ynh_handle_getopts_args "$@"
 
-    mysqldump -u "root" -p"$(cat $MYSQL_ROOT_PWD_FILE)" --single-transaction --skip-dump-date "$database"
+    mysqldump --user="root" --password="$(cat $MYSQL_ROOT_PWD_FILE)" --single-transaction --skip-dump-date "$database"
 }
 
 # Create a user
@@ -225,7 +225,7 @@ ynh_mysql_remove_db () {
     ynh_handle_getopts_args "$@"
 
     local mysql_root_password=$(cat $MYSQL_ROOT_PWD_FILE)
-    if mysqlshow -u root -p$mysql_root_password | grep -q "^| $db_name"
+    if mysqlshow --user=root --password=$mysql_root_password | grep --quiet "^| $db_name"
     then	# Check if the database exists
         ynh_mysql_drop_db $db_name	# Remove the database	
     else
diff --git a/data/helpers.d/network b/data/helpers.d/network
index ca15e6919..2e301090c 100644
--- a/data/helpers.d/network
+++ b/data/helpers.d/network
@@ -17,7 +17,7 @@ ynh_find_port () {
     ynh_handle_getopts_args "$@"
 
     test -n "$port" || ynh_die --message="The argument of ynh_find_port must be a valid port."
-    while ss -nltu | awk '{print$5}' | grep -q -E ":$port$"       # Check if the port is free
+    while ss --numeric --listening --tcp --udp | awk '{print$5}' | grep --quiet --extended-regexp ":$port$"       # Check if the port is free
     do
         port=$((port+1))	# Else, pass to next port
     done
@@ -40,7 +40,7 @@ ynh_port_available () {
     # Manage arguments with getopts
     ynh_handle_getopts_args "$@"
 
-    if ss -nltu | grep -q -w :$port
+    if ss --numeric --listening --tcp --udp | grep --quiet --word-regexp :$port
     then
         return 1
     else
diff --git a/data/helpers.d/nodejs b/data/helpers.d/nodejs
index 2d4ea66dc..cb83e3136 100644
--- a/data/helpers.d/nodejs
+++ b/data/helpers.d/nodejs
@@ -15,7 +15,7 @@ export N_PREFIX="$n_install_dir"
 ynh_install_n () {
     ynh_print_info --message="Installation of N - Node.js version management"
     # Build an app.src for n
-    mkdir -p "../conf"
+    mkdir --parents "../conf"
     echo "SOURCE_URL=https://github.com/tj/n/archive/v4.1.0.tar.gz
 SOURCE_SUM=3983fa3f00d4bf85ba8e21f1a590f6e28938093abe0bb950aeea52b1717471fc" > "../conf/n.src"
     # Download and extract n
@@ -74,7 +74,7 @@ ynh_install_nodejs () {
     ynh_handle_getopts_args "$@"
 
     # Create $n_install_dir
-    mkdir -p "$n_install_dir"
+    mkdir --parents "$n_install_dir"
 
     # Load n path in PATH
     CLEAR_PATH="$n_install_dir/bin:$PATH"
@@ -102,7 +102,7 @@ ynh_install_nodejs () {
     test -x /usr/bin/npm_n && mv /usr/bin/npm_n /usr/bin/npm
 
     # Install the requested version of nodejs
-    uname=$(uname -m)
+    uname=$(uname --machine)
     if [[ $uname =~ aarch64 || $uname =~ arm64 ]]
     then
         n $nodejs_version --arch=arm64
@@ -159,7 +159,7 @@ ynh_remove_nodejs () {
         ynh_secure_remove --file="$n_install_dir"
         ynh_secure_remove --file="/usr/local/n"
         sed --in-place "/N_PREFIX/d" /root/.bashrc
-        rm -f /etc/cron.daily/node_update
+        rm --force /etc/cron.daily/node_update
     fi
 }
 
diff --git a/data/helpers.d/php b/data/helpers.d/php
index c904f8f1b..1bbb6c84b 100644
--- a/data/helpers.d/php
+++ b/data/helpers.d/php
@@ -117,7 +117,7 @@ ynh_add_fpm_config () {
     fi
 
     # Create the directory for fpm pools
-    mkdir -p "$fpm_config_dir/pool.d"
+    mkdir --parents "$fpm_config_dir/pool.d"
 
     ynh_app_setting_set --app=$app --key=fpm_config_dir --value="$fpm_config_dir"
     ynh_app_setting_set --app=$app --key=fpm_service --value="$fpm_service"
@@ -341,7 +341,7 @@ ynh_install_php () {
     fi
 
     # Add an extra repository for those packages
-    ynh_install_extra_repo --repo="https://packages.sury.org/php/ $(lsb_release -sc) main" --key="https://packages.sury.org/php/apt.gpg" --priority=995 --name=extra_php_version
+    ynh_install_extra_repo --repo="https://packages.sury.org/php/ $(ynh_get_debian_release) main" --key="https://packages.sury.org/php/apt.gpg" --priority=995 --name=extra_php_version
 
     # Install requested dependencies from this extra repository.
     # Install php-fpm first, otherwise php will install apache as a dependency.
diff --git a/data/helpers.d/setting b/data/helpers.d/setting
index eca529069..86634dcc3 100644
--- a/data/helpers.d/setting
+++ b/data/helpers.d/setting
@@ -231,7 +231,7 @@ ynh_permission_exists() {
     local permission
     ynh_handle_getopts_args "$@"
 
-    yunohost user permission list -s | grep -w -q "$app.$permission"
+    yunohost user permission list --short | grep --word-regexp --quiet "$app.$permission"
 }
 
 # Redefine the url associated to a permission
@@ -311,5 +311,5 @@ ynh_permission_has_user() {
         return 1
     fi
 
-    yunohost user permission info "$app.$permission" | grep -w -q "$user"
+    yunohost user permission info "$app.$permission" | grep --word-regexp --quiet "$user"
 }
diff --git a/data/helpers.d/string b/data/helpers.d/string
index 76c3b37e4..dd318b4de 100644
--- a/data/helpers.d/string
+++ b/data/helpers.d/string
@@ -18,8 +18,8 @@ ynh_string_random() {
     length=${length:-24}
 
     dd if=/dev/urandom bs=1 count=1000 2> /dev/null \
-        | tr -c -d 'A-Za-z0-9' \
-        | sed -n 's/\(.\{'"$length"'\}\).*/\1/p'
+        | tr --complement --delete 'A-Za-z0-9' \
+        | sed --quiet 's/\(.\{'"$length"'\}\).*/\1/p'
 }
 
 # Substitute/replace a string (or expression) by another in a file
diff --git a/data/helpers.d/systemd b/data/helpers.d/systemd
index 6257b9138..b6c4722af 100644
--- a/data/helpers.d/systemd
+++ b/data/helpers.d/systemd
@@ -112,7 +112,7 @@ ynh_systemd_action() {
             local pid_tail=$!
         else
             # Read the specified log file
-            tail -F -n0 "$log_path" > "$templog" 2>&1 &
+            tail --follow --retry --lines=0 "$log_path" > "$templog" 2>&1 &
             # Get the PID of the tail command
             local pid_tail=$!
         fi
@@ -170,7 +170,7 @@ ynh_clean_check_starting () {
     if [ -n "$pid_tail" ]
     then
         # Stop the execution of tail.
-        kill -s 15 $pid_tail 2>&1
+        kill --signal 15 $pid_tail 2>&1
     fi
     if [ -n "$templog" ]
     then
diff --git a/data/helpers.d/user b/data/helpers.d/user
index 0b964c7c0..ff6c4e6ea 100644
--- a/data/helpers.d/user
+++ b/data/helpers.d/user
@@ -16,7 +16,7 @@ ynh_user_exists() {
     # Manage arguments with getopts
     ynh_handle_getopts_args "$@"
 
-    yunohost user list --output-as json | grep -q "\"username\": \"${username}\""
+    yunohost user list --output-as json | grep --quiet "\"username\": \"${username}\""
 }
 
 # Retrieve a YunoHost user information
@@ -116,7 +116,7 @@ ynh_system_user_create () {
     then	# If the user doesn't exist
         if [ -n "$home_dir" ]
         then	# If a home dir is mentioned
-            local user_home_dir="-d $home_dir"
+            local user_home_dir="--home-dir $home_dir"
         else
             local user_home_dir="--no-create-home"
         fi
diff --git a/data/helpers.d/utils b/data/helpers.d/utils
index 2ad05f93c..41cef98c2 100644
--- a/data/helpers.d/utils
+++ b/data/helpers.d/utils
@@ -23,7 +23,9 @@ ynh_exit_properly () {
     fi
 
     trap '' EXIT	# Ignore new exit signals
-    set +eu	# Do not exit anymore if a command fail or if a variable is empty
+    # Do not exit anymore if a command fail or if a variable is empty
+    set +o errexit  # set +e
+    set +o nounset  # set +u
 
     # Small tempo to avoid the next message being mixed up with other DEBUG messages
     sleep 0.5
@@ -46,7 +48,8 @@ ynh_exit_properly () {
 #
 # Requires YunoHost version 2.6.4 or higher.
 ynh_abort_if_errors () {
-    set -eu	# Exit if a command fail, and if a variable is used unset.
+    set -o errexit  # set -e; Exit if a command fail
+    set -o nounset  # set -u; And if a variable is used unset
     trap ynh_exit_properly EXIT	# Capturing exit signals on shell script
 }
 
@@ -115,13 +118,13 @@ ynh_setup_source () {
 
     # Load value from configuration file (see above for a small doc about this file
     # format)
-    local src_url=$(grep 'SOURCE_URL=' "$src_file_path" | cut -d= -f2-)
-    local src_sum=$(grep 'SOURCE_SUM=' "$src_file_path" | cut -d= -f2-)
-    local src_sumprg=$(grep 'SOURCE_SUM_PRG=' "$src_file_path" | cut -d= -f2-)
-    local src_format=$(grep 'SOURCE_FORMAT=' "$src_file_path" | cut -d= -f2-)
-    local src_extract=$(grep 'SOURCE_EXTRACT=' "$src_file_path" | cut -d= -f2-)
-    local src_in_subdir=$(grep 'SOURCE_IN_SUBDIR=' "$src_file_path" | cut -d= -f2-)
-    local src_filename=$(grep 'SOURCE_FILENAME=' "$src_file_path" | cut -d= -f2-)
+    local src_url=$(grep 'SOURCE_URL=' "$src_file_path" | cut --delimiter='=' --fields=2-)
+    local src_sum=$(grep 'SOURCE_SUM=' "$src_file_path" | cut --delimiter='=' --fields=2-)
+    local src_sumprg=$(grep 'SOURCE_SUM_PRG=' "$src_file_path" | cut --delimiter='=' --fields=2-)
+    local src_format=$(grep 'SOURCE_FORMAT=' "$src_file_path" | cut --delimiter='=' --fields=2-)
+    local src_extract=$(grep 'SOURCE_EXTRACT=' "$src_file_path" | cut --delimiter='=' --fields=2-)
+    local src_in_subdir=$(grep 'SOURCE_IN_SUBDIR=' "$src_file_path" | cut --delimiter='=' --fields=2-)
+    local src_filename=$(grep 'SOURCE_FILENAME=' "$src_file_path" | cut --delimiter='=' --fields=2-)
 
     # Default value
     src_sumprg=${src_sumprg:-sha256sum}
@@ -138,15 +141,15 @@ ynh_setup_source () {
     then    # Use the local source file if it is present
         cp $local_src $src_filename
     else    # If not, download the source
-        local out=`wget -nv -O $src_filename $src_url 2>&1` || ynh_print_err --message="$out"
+        local out=`wget --no-verbose --output-document=$src_filename $src_url 2>&1` || ynh_print_err --message="$out"
     fi
 
     # Check the control sum
-    echo "${src_sum} ${src_filename}" | ${src_sumprg} -c --status \
+    echo "${src_sum} ${src_filename}" | ${src_sumprg} --check --status \
         || ynh_die --message="Corrupt source"
 
     # Extract source into the app dir
-    mkdir -p "$dest_dir"
+    mkdir --parents "$dest_dir"
 
     if ! "$src_extract"
     then
@@ -157,9 +160,9 @@ ynh_setup_source () {
         # Using of a temp directory, because unzip doesn't manage --strip-components
         if $src_in_subdir
         then
-            local tmp_dir=$(mktemp -d)
+            local tmp_dir=$(mktemp --directory)
             unzip -quo $src_filename -d "$tmp_dir"
-            cp -a $tmp_dir/*/. "$dest_dir"
+            cp --archive $tmp_dir/*/. "$dest_dir"
             ynh_secure_remove --file="$tmp_dir"
         else
             unzip -quo $src_filename -d "$dest_dir"
@@ -178,7 +181,7 @@ ynh_setup_source () {
         fi
         if [[ "$src_format" =~ ^tar.gz|tar.bz2|tar.xz$ ]]
         then
-            tar -xf $src_filename -C "$dest_dir" $strip
+            tar --extract --file=$src_filename --directory="$dest_dir" $strip
         else
             ynh_die --message="Archive format unrecognized."
         fi
@@ -196,7 +199,7 @@ ynh_setup_source () {
 
     # Add supplementary files
     if test -e "$YNH_CWD/../sources/extra_files/${source_id}"; then
-        cp -a $YNH_CWD/../sources/extra_files/$source_id/. "$dest_dir"
+        cp --archive $YNH_CWD/../sources/extra_files/$source_id/. "$dest_dir"
     fi
 }
 
@@ -247,7 +250,7 @@ ynh_local_curl () {
     chmod 700 $cookiefile
 
     # Curl the URL
-    curl --silent --show-error -kL -H "Host: $domain" --resolve $domain:443:127.0.0.1 $POST_data "$full_page_url" --cookie-jar $cookiefile --cookie $cookiefile
+    curl --silent --show-error --insecure --location --header "Host: $domain" --resolve $domain:443:127.0.0.1 $POST_data "$full_page_url" --cookie-jar $cookiefile --cookie $cookiefile
 }
 
 # Render templates with Jinja2
@@ -290,7 +293,7 @@ ynh_mkdir_tmp() {
     ynh_print_warn --message="The helper ynh_mkdir_tmp is deprecated."
     ynh_print_warn --message="You should use 'mktemp -d' instead and manage permissions \
 properly with chmod/chown."
-    local TMP_DIR=$(mktemp -d)
+    local TMP_DIR=$(mktemp --directory)
 
     # Give rights to other users could be a security risk.
     # But for retrocompatibility we need it. (This helpers is deprecated)
@@ -334,7 +337,7 @@ ynh_secure_remove () {
         ynh_print_warn --message="Not deleting '$file' because it is not an acceptable path to delete."
     elif [ -e "$file" ]
     then
-        rm -R "$file"
+        rm --recursive "$file"
     else
         ynh_print_info --message="'$file' wasn't deleted because it doesn't exist."
     fi