diff --git a/helpers/helpers.v2.1.d/go b/helpers/helpers.v2.1.d/go
index 22797397e..68f5ceaad 100644
--- a/helpers/helpers.v2.1.d/go
+++ b/helpers/helpers.v2.1.d/go
@@ -8,19 +8,18 @@ ynh_go_try_bash_extension() {
   fi
 }
 
-goenv_install_dir="/opt/goenv"
-go_version_path="$goenv_install_dir/versions"
+readonly GOENV_INSTALL_DIR="/opt/goenv"
 # goenv_ROOT is the directory of goenv, it needs to be loaded as a environment variable.
-export GOENV_ROOT="$goenv_install_dir"
+export GOENV_ROOT="$GOENV_INSTALL_DIR"
 
 _ynh_load_go_in_path_and_other_tweaks() {
 
     # Get the absolute path of this version of go
-    local go_path="$go_version_path/$app/bin"
+    go_dir="$GOENV_INSTALL_DIR/versions/$app/bin"
 
     # Load the path of this version of go in $PATH
-    if [[ :$PATH: != *":$go_path"* ]]; then
-        PATH="$go_path:$PATH"
+    if [[ :$PATH: != *":$go_dir"* ]]; then
+        PATH="$go_dir:$PATH"
     fi
 
     # Export PATH such that it's available through sudo -E / ynh_exec_as $app
@@ -32,7 +31,7 @@ _ynh_load_go_in_path_and_other_tweaks() {
 
     # Sets the local application-specific go version
     pushd ${install_dir}
-        $goenv_install_dir/bin/goenv local $go_version
+        $GOENV_INSTALL_DIR/bin/goenv local $go_version
     popd
 }
 
@@ -56,7 +55,7 @@ ynh_go_install () {
     [[ -n "${go_version:-}" ]] || ynh_die "\$go_version should be defined prior to calling ynh_go_install"
 
     # Load goenv path in PATH
-    local CLEAR_PATH="$goenv_install_dir/bin:$PATH"
+    local CLEAR_PATH="$GOENV_INSTALL_DIR/bin:$PATH"
 
     # Remove /usr/local/bin in PATH in case of Go prior installation
     PATH=$(echo $CLEAR_PATH | sed 's@/usr/local/bin:@@')
@@ -65,9 +64,9 @@ ynh_go_install () {
     test -x /usr/bin/go && mv /usr/bin/go /usr/bin/go_goenv
 
     # Install or update goenv
-    mkdir -p $goenv_install_dir
-    pushd "$goenv_install_dir"
-        if ! [ -x "$goenv_install_dir/bin/goenv" ]; then
+    mkdir -p $GOENV_INSTALL_DIR
+    pushd "$GOENV_INSTALL_DIR"
+        if ! [ -x "$GOENV_INSTALL_DIR/bin/goenv" ]; then
             ynh_print_info "Downloading goenv..."
             git init -q
             git remote add origin https://github.com/syndbg/goenv.git 
@@ -78,13 +77,13 @@ ynh_go_install () {
         local git_latest_tag=$(git describe --tags "$(git rev-list --tags --max-count=1)")
         git checkout -q "$git_latest_tag"
         ynh_go_try_bash_extension
-        goenv=$goenv_install_dir/bin/goenv
+        goenv=$GOENV_INSTALL_DIR/bin/goenv
     popd
 
     # Install or update xxenv-latest
-    mkdir -p "$goenv_install_dir/plugins/xxenv-latest"
-    pushd "$goenv_install_dir/plugins/xxenv-latest"
-        if ! [ -x "$goenv_install_dir/plugins/xxenv-latest/bin/goenv-latest" ]; then
+    mkdir -p "$GOENV_INSTALL_DIR/plugins/xxenv-latest"
+    pushd "$GOENV_INSTALL_DIR/plugins/xxenv-latest"
+        if ! [ -x "$GOENV_INSTALL_DIR/plugins/xxenv-latest/bin/goenv-latest" ]; then
             ynh_print_info "Downloading xxenv-latest..."
             git init -q
             git remote add origin https://github.com/momo-lab/xxenv-latest.git 
@@ -97,10 +96,10 @@ ynh_go_install () {
     popd
 
     # Enable caching
-    mkdir -p "${goenv_install_dir}/cache"
+    mkdir -p "${GOENV_INSTALL_DIR}/cache"
 
     # Create shims directory if needed
-    mkdir -p "${goenv_install_dir}/shims"
+    mkdir -p "${GOENV_INSTALL_DIR}/shims"
 
     # Restore /usr/local/bin in PATH
     PATH=$CLEAR_PATH
@@ -122,8 +121,8 @@ ynh_go_install () {
 
     # Set environment for Go users
     echo  "#goenv
-export GOENV_ROOT=$goenv_install_dir
-export PATH=\"$goenv_install_dir/bin:$PATH\"
+export GOENV_ROOT=$GOENV_INSTALL_DIR
+export PATH=\"$GOENV_INSTALL_DIR/bin:$PATH\"
 eval \"\$(goenv init -)\"
 #goenv" > /etc/profile.d/goenv.sh
 
@@ -142,7 +141,7 @@ ynh_go_remove () {
     local go_version=$(ynh_app_setting_get --key="go_version")
 
     # Load goenv path in PATH
-    local CLEAR_PATH="$goenv_install_dir/bin:$PATH"
+    local CLEAR_PATH="$GOENV_INSTALL_DIR/bin:$PATH"
 
     # Remove /usr/local/bin in PATH in case of Go prior installation
     PATH=$(echo $CLEAR_PATH | sed 's@/usr/local/bin:@@')
@@ -182,7 +181,7 @@ _ynh_go_cleanup () {
         if ! `echo ${required_go_versions} | grep "${installed_go_version}" 1>/dev/null 2>&1`
         then
             ynh_print_info "Removing of Go-$installed_go_version"
-            $goenv_install_dir/bin/goenv uninstall --force "$installed_go_version"
+            $GOENV_INSTALL_DIR/bin/goenv uninstall --force "$installed_go_version"
         fi
     done
 
@@ -191,7 +190,7 @@ _ynh_go_cleanup () {
     then
         # Remove goenv environment configuration
         ynh_print_info "Removing of goenv"
-        ynh_safe_rm "$goenv_install_dir"
+        ynh_safe_rm "$GOENV_INSTALL_DIR"
         ynh_safe_rm "/etc/profile.d/goenv.sh"
     fi
 }
diff --git a/helpers/helpers.v2.1.d/nodejs b/helpers/helpers.v2.1.d/nodejs
index e8eecb829..5e5b13f4e 100644
--- a/helpers/helpers.v2.1.d/nodejs
+++ b/helpers/helpers.v2.1.d/nodejs
@@ -1,18 +1,17 @@
 #!/bin/bash
 
-n_install_dir="/opt/node_n"
-node_version_path="$n_install_dir/n/versions/node"
+readonly N_INSTALL_DIR="/opt/node_n"
 # N_PREFIX is the directory of n, it needs to be loaded as a environment variable.
-export N_PREFIX="$n_install_dir"
+export N_PREFIX="$N_INSTALL_DIR"
 
 _ynh_load_nodejs_in_path_and_other_tweaks() {
 
     # Get the absolute path of this version of node
-    local nodejs_path="$node_version_path/$nodejs_version/bin"
+    nodejs_dir="$N_INSTALL_DIR/n/versions/node/$nodejs_version/bin"
 
     # Load the path of this version of node in $PATH
-    if [[ :$PATH: != *":$nodejs_path"* ]]; then
-        PATH="$nodejs_path:$PATH"
+    if [[ :$PATH: != *":$nodejs_dir"* ]]; then
+        PATH="$nodejs_dir:$PATH"
     fi
 
     # Export PATH such that it's available through sudo -E / ynh_exec_as $app
@@ -46,11 +45,11 @@ ynh_nodejs_install() {
 
     [[ -n "${nodejs_version:-}" ]] || ynh_die "\$nodejs_version should be defined prior to calling ynh_nodejs_install"
 
-    # Create $n_install_dir
-    mkdir --parents "$n_install_dir"
+    # Create $N_INSTALL_DIR
+    mkdir --parents "$N_INSTALL_DIR"
 
     # Load n path in PATH
-    CLEAR_PATH="$n_install_dir/bin:$PATH"
+    CLEAR_PATH="$N_INSTALL_DIR/bin:$PATH"
     # Remove /usr/local/bin in PATH in case of node prior installation
     PATH=$(echo $CLEAR_PATH | sed 's@/usr/local/bin:@@')
 
@@ -59,10 +58,10 @@ ynh_nodejs_install() {
     test -x /usr/bin/npm && mv /usr/bin/npm /usr/bin/npm_n
 
     # Install (or update if YunoHost vendor/ folder updated since last install) n
-    mkdir -p $n_install_dir/bin/
-    cp "$YNH_HELPERS_DIR/vendor/n/n" $n_install_dir/bin/n
+    mkdir -p $N_INSTALL_DIR/bin/
+    cp "$YNH_HELPERS_DIR/vendor/n/n" $N_INSTALL_DIR/bin/n
     # Tweak for n to understand it's installed in $N_PREFIX
-    ynh_replace --match="^N_PREFIX=\${N_PREFIX-.*}$" --replace="N_PREFIX=\${N_PREFIX-$N_PREFIX}" --file="$n_install_dir/bin/n"
+    ynh_replace --match="^N_PREFIX=\${N_PREFIX-.*}$" --replace="N_PREFIX=\${N_PREFIX-$N_PREFIX}" --file="$N_INSTALL_DIR/bin/n"
 
     # Restore /usr/local/bin in PATH
     PATH=$CLEAR_PATH
@@ -80,16 +79,18 @@ ynh_nodejs_install() {
     fi
 
     # Find the last "real" version for this major version of node.
-    real_nodejs_version=$(find $node_version_path/$nodejs_version* -maxdepth 0 | sort --version-sort | tail --lines=1)
+    real_nodejs_version=$(find $N_INSTALL_DIR/n/versions/node/$nodejs_version* -maxdepth 0 | sort --version-sort | tail --lines=1)
     real_nodejs_version=$(basename $real_nodejs_version)
 
     # Create a symbolic link for this major version if the file doesn't already exist
-    if [ ! -e "$node_version_path/$nodejs_version" ]; then
-        ln --symbolic --force --no-target-directory $node_version_path/$real_nodejs_version $node_version_path/$nodejs_version
+    if [ ! -e "$N_INSTALL_DIR/n/versions/node/$nodejs_version" ]; then
+        ln --symbolic --force --no-target-directory \
+            $N_INSTALL_DIR/n/versions/node/$real_nodejs_version \
+            $N_INSTALL_DIR/n/versions/node/$nodejs_version
     fi
 
     # Store the ID of this app and the version of node requested for it
-    echo "$YNH_APP_INSTANCE_NAME:$nodejs_version" | tee --append "$n_install_dir/ynh_app_version"
+    echo "$YNH_APP_INSTANCE_NAME:$nodejs_version" | tee --append "$N_INSTALL_DIR/ynh_app_version"
 
     # Store nodejs_version into the config of this app
     ynh_app_setting_set --key=nodejs_version --value=$nodejs_version
@@ -111,17 +112,16 @@ ynh_nodejs_remove() {
     [[ -n "${nodejs_version:-}" ]] || ynh_die "\$nodejs_version should be defined prior to calling ynh_nodejs_remove"
 
     # Remove the line for this app
-    sed --in-place "/$YNH_APP_INSTANCE_NAME:$nodejs_version/d" "$n_install_dir/ynh_app_version"
+    sed --in-place "/$YNH_APP_INSTANCE_NAME:$nodejs_version/d" "$N_INSTALL_DIR/ynh_app_version"
 
     # If no other app uses this version of nodejs, remove it.
-    if ! grep --quiet "$nodejs_version" "$n_install_dir/ynh_app_version"; then
-        $n_install_dir/bin/n rm $nodejs_version
+    if ! grep --quiet "$nodejs_version" "$N_INSTALL_DIR/ynh_app_version"; then
+        $N_INSTALL_DIR/bin/n rm $nodejs_version
     fi
 
     # If no other app uses n, remove n
-    if [ ! -s "$n_install_dir/ynh_app_version" ]; then
-        ynh_safe_rm "$n_install_dir"
-        ynh_safe_rm "/usr/local/n"
+    if [ ! -s "$N_INSTALL_DIR/ynh_app_version" ]; then
+        ynh_safe_rm "$N_INSTALL_DIR"
         sed --in-place "/N_PREFIX/d" /root/.bashrc
     fi
 }
diff --git a/helpers/helpers.v2.1.d/ruby b/helpers/helpers.v2.1.d/ruby
index dae25c6fd..c33967a9f 100644
--- a/helpers/helpers.v2.1.d/ruby
+++ b/helpers/helpers.v2.1.d/ruby
@@ -1,20 +1,19 @@
 #!/bin/bash
 
-rbenv_install_dir="/opt/rbenv"
-ruby_version_path="$rbenv_install_dir/versions"
+readonly RBENV_INSTALL_DIR="/opt/rbenv"
 
 # RBENV_ROOT is the directory of rbenv, it needs to be loaded as a environment variable.
-export RBENV_ROOT="$rbenv_install_dir"
-export rbenv_root="$rbenv_install_dir"
+export RBENV_ROOT="$RBENV_INSTALL_DIR"
+export rbenv_root="$RBENV_INSTALL_DIR"
 
 _ynh_load_ruby_in_path_and_other_tweaks() {
 
     # Get the absolute path of this version of Ruby
-    local ruby_path="$ruby_version_path/$app/bin"
+    ruby_dir="$RBENV_INSTALL_DIR/versions/$app/bin"
 
     # Load the path of this version of ruby in $PATH
-    if [[ :$PATH: != *":$ruby_path"* ]]; then
-        PATH="$ruby_path:$PATH"
+    if [[ :$PATH: != *":$ruby_dir"* ]]; then
+        PATH="$ruby_dir:$PATH"
     fi
 
     # Export PATH such that it's available through sudo -E / ynh_exec_as $app
@@ -26,7 +25,7 @@ _ynh_load_ruby_in_path_and_other_tweaks() {
 
     # Sets the local application-specific Ruby version
     pushd ${install_dir}
-        $rbenv_install_dir/bin/rbenv local $ruby_version
+        $RBENV_INSTALL_DIR/bin/rbenv local $ruby_version
     popd
 }
 
@@ -55,7 +54,7 @@ ynh_ruby_install () {
     [[ -n "${ruby_version:-}" ]] || ynh_die "\$ruby_version should be defined prior to calling ynh_ruby_install"
 
     # Load rbenv path in PATH
-    local CLEAR_PATH="$rbenv_install_dir/bin:$PATH"
+    local CLEAR_PATH="$RBENV_INSTALL_DIR/bin:$PATH"
 
     # Remove /usr/local/bin in PATH in case of Ruby prior installation
     PATH=$(echo $CLEAR_PATH | sed 's@/usr/local/bin:@@')
@@ -64,8 +63,8 @@ ynh_ruby_install () {
     test -x /usr/bin/ruby && mv /usr/bin/ruby /usr/bin/ruby_rbenv
 
     # Install or update rbenv
-    mkdir -p $rbenv_install_dir
-    rbenv="$(command -v rbenv $rbenv_install_dir/bin/rbenv | grep "$rbenv_install_dir/bin/rbenv" | head -1)"
+    mkdir -p $RBENV_INSTALL_DIR
+    rbenv="$(command -v rbenv $RBENV_INSTALL_DIR/bin/rbenv | grep "$RBENV_INSTALL_DIR/bin/rbenv" | head -1)"
     if [ -n "$rbenv" ]; then
         pushd "${rbenv%/*/*}"
             if git remote -v 2>/dev/null | grep "https://github.com/rbenv/rbenv.git"; then
@@ -75,30 +74,30 @@ ynh_ruby_install () {
             else
                 echo "Reinstalling rbenv..."
                 cd ..
-                ynh_safe_rm $rbenv_install_dir
-                mkdir -p $rbenv_install_dir
-                cd $rbenv_install_dir
+                ynh_safe_rm $RBENV_INSTALL_DIR
+                mkdir -p $RBENV_INSTALL_DIR
+                cd $RBENV_INSTALL_DIR
                 git init -q
                 git remote add -f -t master origin https://github.com/rbenv/rbenv.git > /dev/null 2>&1
                 git checkout -q -b master origin/master
                 ynh_ruby_try_bash_extension
-                rbenv=$rbenv_install_dir/bin/rbenv
+                rbenv=$RBENV_INSTALL_DIR/bin/rbenv
             fi
         popd
     else
         echo "Installing rbenv..."
-        pushd $rbenv_install_dir
+        pushd $RBENV_INSTALL_DIR
             git init -q
             git remote add -f -t master origin https://github.com/rbenv/rbenv.git > /dev/null 2>&1
             git checkout -q -b master origin/master
             ynh_ruby_try_bash_extension
-            rbenv=$rbenv_install_dir/bin/rbenv
+            rbenv=$RBENV_INSTALL_DIR/bin/rbenv
         popd
     fi
 
-    mkdir -p "${rbenv_install_dir}/plugins"
+    mkdir -p "${RBENV_INSTALL_DIR}/plugins"
 
-    ruby_build="$(command -v "$rbenv_install_dir"/plugins/*/bin/rbenv-install rbenv-install | head -1)"
+    ruby_build="$(command -v "$RBENV_INSTALL_DIR"/plugins/*/bin/rbenv-install rbenv-install | head -1)"
     if [ -n "$ruby_build" ]; then
         pushd "${ruby_build%/*/*}"
             if git remote -v 2>/dev/null | grep "https://github.com/rbenv/ruby-build.git"; then
@@ -108,10 +107,10 @@ ynh_ruby_install () {
         popd
     else
         echo "Installing ruby-build..."
-        git clone -q https://github.com/rbenv/ruby-build.git "${rbenv_install_dir}/plugins/ruby-build"
+        git clone -q https://github.com/rbenv/ruby-build.git "${RBENV_INSTALL_DIR}/plugins/ruby-build"
     fi
 
-    rbenv_alias="$(command -v "$rbenv_install_dir"/plugins/*/bin/rbenv-alias rbenv-alias | head -1)"
+    rbenv_alias="$(command -v "$RBENV_INSTALL_DIR"/plugins/*/bin/rbenv-alias rbenv-alias | head -1)"
     if [ -n "$rbenv_alias" ]; then
         pushd "${rbenv_alias%/*/*}"
             if git remote -v 2>/dev/null | grep "https://github.com/tpope/rbenv-aliases.git"; then
@@ -121,10 +120,10 @@ ynh_ruby_install () {
         popd
     else
         echo "Installing rbenv-aliases..."
-        git clone -q https://github.com/tpope/rbenv-aliases.git "${rbenv_install_dir}/plugins/rbenv-aliase"
+        git clone -q https://github.com/tpope/rbenv-aliases.git "${RBENV_INSTALL_DIR}/plugins/rbenv-aliase"
     fi
 
-    rbenv_latest="$(command -v "$rbenv_install_dir"/plugins/*/bin/rbenv-latest rbenv-latest | head -1)"
+    rbenv_latest="$(command -v "$RBENV_INSTALL_DIR"/plugins/*/bin/rbenv-latest rbenv-latest | head -1)"
     if [ -n "$rbenv_latest" ]; then
         pushd "${rbenv_latest%/*/*}"
             if git remote -v 2>/dev/null | grep "https://github.com/momo-lab/xxenv-latest.git"; then
@@ -134,14 +133,14 @@ ynh_ruby_install () {
         popd
     else
         echo "Installing xxenv-latest..."
-        git clone -q https://github.com/momo-lab/xxenv-latest.git "${rbenv_install_dir}/plugins/xxenv-latest"
+        git clone -q https://github.com/momo-lab/xxenv-latest.git "${RBENV_INSTALL_DIR}/plugins/xxenv-latest"
     fi
 
     # Enable caching
-    mkdir -p "${rbenv_install_dir}/cache"
+    mkdir -p "${RBENV_INSTALL_DIR}/cache"
 
     # Create shims directory if needed
-    mkdir -p "${rbenv_install_dir}/shims"
+    mkdir -p "${RBENV_INSTALL_DIR}/shims"
 
     # Restore /usr/local/bin in PATH
     PATH=$CLEAR_PATH
@@ -175,8 +174,8 @@ ynh_ruby_install () {
 
     # Set environment for Ruby users
     echo  "#rbenv
-export RBENV_ROOT=$rbenv_install_dir
-export PATH=\"$rbenv_install_dir/bin:$PATH\"
+export RBENV_ROOT=$RBENV_INSTALL_DIR
+export PATH=\"$RBENV_INSTALL_DIR/bin:$PATH\"
 eval \"\$(rbenv init -)\"
 #rbenv" > /etc/profile.d/rbenv.sh
 
@@ -192,10 +191,11 @@ eval \"\$(rbenv init -)\"
 #
 # usage: ynh_ruby_remove
 ynh_ruby_remove () {
-    local ruby_version=$(ynh_app_setting_get --key=ruby_version)
+
+    [[ -n "${ruby_version:-}" ]] || ynh_die "\$ruby_version should be defined prior to calling ynh_ruby_remove"
 
     # Load rbenv path in PATH
-    local CLEAR_PATH="$rbenv_install_dir/bin:$PATH"
+    local CLEAR_PATH="$RBENV_INSTALL_DIR/bin:$PATH"
 
     # Remove /usr/local/bin in PATH in case of Ruby prior installation
     PATH=$(echo $CLEAR_PATH | sed 's@/usr/local/bin:@@')
@@ -235,7 +235,7 @@ _ynh_ruby_cleanup () {
         if ! echo ${required_ruby_versions} | grep -q "${installed_ruby_version}"
         then
             echo "Removing Ruby-$installed_ruby_version"
-            $rbenv_install_dir/bin/rbenv uninstall --force $installed_ruby_version
+            $RBENV_INSTALL_DIR/bin/rbenv uninstall --force $installed_ruby_version
         fi
     done
 
@@ -244,7 +244,7 @@ _ynh_ruby_cleanup () {
     then
         # Remove rbenv environment configuration
         echo "Removing rbenv"
-        ynh_safe_rm "$rbenv_install_dir"
+        ynh_safe_rm "$RBENV_INSTALL_DIR"
         ynh_safe_rm "/etc/profile.d/rbenv.sh"
     fi
 }