diff --git a/scripts/_common.sh b/scripts/_common.sh
index cc972e8..e90c0a3 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -4,13 +4,342 @@
 # COMMON VARIABLES
 #=================================================
 
-go_version=1.20
+go_version=1.18
 node_version=16
 
 #=================================================
 # PERSONAL HELPERS
 #=================================================
 
+function set_go_vars {
+    ynh_use_go
+
+    export GOPATH="$install_dir/build/go"
+    export GOCACHE="$install_dir/build/.cache"
+
+    go_shims_path=$goenv_install_dir/shims
+    go_path_full="$go_shims_path":"$(sudo -u $app bash -c 'echo $PATH')"
+    heif_lib_path="$install_dir/local/lib":"$(sudo -u $app bash -c 'echo $LIBRARY_PATH')"
+    heif_ld_lib_path="$install_dir/local/lib":"$(sudo -u $app bash -c 'echo $LD_LIBRARY_PATH')"
+    heif_cgo_cflags="-I$install_dir/local/include"
+}
+
+function build_libheif {
+    export GOPATH="$install_dir/build/go"
+    export GOCACHE="$install_dir/build/.cache"
+
+    pushd "$install_dir/libheif" || ynh_die
+        # mkdir -p "$install_dir/local"
+        # chown -R $app:$app "$install_dir/local"
+        ynh_exec_as "$app" ./autogen.sh 2>&1
+        ynh_exec_as "$app" ./configure --prefix="$install_dir/local" --disable-gdk-pixbuf 2>&1
+        ynh_exec_as "$app" make clean 2>&1
+        ynh_exec_as "$app" make 2>&1
+        ynh_exec_as "$app" make install 2>&1
+        ynh_exec_as "$app" make clean 2>&1
+    popd || ynh_die
+}
+
+function build_api {
+    set_go_vars
+
+    gobuild_env=(
+        "PATH=$go_path_full"
+        "LIBRARY_PATH=$heif_lib_path"
+        "LD_LIBRARY_PATH=$heif_ld_lib_path"
+        "CGO_CFLAGS=$heif_cgo_cflags"
+        "GOENV_VERSION=$go_version"
+        CGO_ENABLED=1
+    )
+
+    pushd "$install_dir/sources/api" || ynh_die
+        set +e
+        for i in {1..5}; do
+            ynh_exec_as "$app" env "${gobuild_env[@]}" go mod download 2>&1 && break
+            sleep 5
+        done
+        set -e
+        ynh_exec_as "$app" env "${gobuild_env[@]}" go install github.com/mattn/go-sqlite3 github.com/Kagami/go-face 2>&1
+        ynh_exec_as "$app" env "${gobuild_env[@]}" go build -o photoview . 2>&1
+    popd || ynh_die
+
+    cp -T "$install_dir/sources/api/photoview" "$install_dir/output/photoview"
+    cp -rT "$install_dir/sources/api/data" "$install_dir/output/data"
+}
+
+function build_ui {
+    ynh_use_nodejs
+
+    pushd "$install_dir/sources/ui" || ynh_die
+        ynh_replace_string -m "cd .. && " -r "" -f "package.json"
+        # chown -R "$app:$app" $install_dir
+        ynh_exec_as "$app" touch ".yarnrc"
+        ynh_exec_as "$app" env "$ynh_node_load_PATH" yarn --cache-folder "./yarn-cache" --use-yarnrc ".yarnrc" import 2>&1
+        # ynh_exec_as "$app" env "$ynh_node_load_PATH" yarn --cache-folder "./yarn-cache" --use-yarnrc ".yarnrc" add husky 2>&1
+        ynh_exec_as "$app" env "$ynh_node_load_PATH" yarn --cache-folder "./yarn-cache" --use-yarnrc ".yarnrc" install --production 2>&1
+        ynh_exec_as "$app" env "$ynh_node_load_PATH" yarn --cache-folder "./yarn-cache" --use-yarnrc ".yarnrc" add graphql --ignore-engines 2>&1
+        ynh_exec_as "$app" env "$ynh_node_load_PATH" yarn --cache-folder "./yarn-cache" --use-yarnrc ".yarnrc" run build --public-url "$path" 2>&1
+        # ynh_exec_as "$app" env "$ynh_node_load_PATH" NODE_ENV=production "$ynh_npm" install
+        # ynh_exec_as "$app" env "$ynh_node_load_PATH" NODE_ENV=production "$ynh_npm" run build
+    popd || ynh_die
+
+    cp -rT "$install_dir/sources/ui/build" "$install_dir/output/ui"
+}
+
+function cleanup_sources {
+    ynh_secure_remove --file="$install_dir/libheif"
+    ynh_secure_remove --file="$install_dir/sources"
+    ynh_secure_remove --file="$install_dir/go"
+    ynh_secure_remove --file="$install_dir/.cache/go-build"
+}
+
+#=================================================
+# EXPERIMENTAL HELPERS
+#=================================================
+
+#!/bin/bash
+
+ynh_go_try_bash_extension() {
+    if [ -x src/configure ]; then
+        src/configure && make -C src || {
+            ynh_print_info --message="Optional bash extension failed to build, but things will still work normally."
+        }
+    fi
+}
+
+goenv_install_dir="/opt/goenv"
+go_version_path="$goenv_install_dir/versions"
+# goenv_ROOT is the directory of goenv, it needs to be loaded as a environment variable.
+export GOENV_ROOT="$goenv_install_dir"
+
+# Load the version of Go for an app, and set variables.
+#
+# ynh_use_go has to be used in any app scripts before using Go for the first time.
+# This helper will provide alias and variables to use in your scripts.
+#
+# To use gem or Go, use the alias `ynh_gem` and `ynh_go`
+# Those alias will use the correct version installed for the app
+# For example: use `ynh_gem install` instead of `gem install`
+#
+# With `sudo` or `ynh_exec_as`, use instead the fallback variables `$ynh_gem` and `$ynh_go`
+# And propagate $PATH to sudo with $ynh_go_load_path
+# Exemple: `ynh_exec_as $app $ynh_go_load_path $ynh_gem install`
+#
+# $PATH contains the path of the requested version of Go.
+# However, $PATH is duplicated into $go_path to outlast any manipulation of $PATH
+# You can use the variable `$ynh_go_load_path` to quickly load your Go version
+#   in $PATH for an usage into a separate script.
+# Exemple: $ynh_go_load_path $install_dir/script_that_use_gem.sh`
+#
+#
+# Finally, to start a Go service with the correct version, 2 solutions
+#   Either the app is dependent of Go or gem, but does not called it directly.
+#   In such situation, you need to load PATH
+#       `Environment="__YNH_GO_LOAD_ENV_PATH__"`
+#       `ExecStart=__INSTALL_DIR__/my_app`
+#        You will replace __YNH_GO_LOAD_ENV_PATH__ with $ynh_go_load_path
+#
+#   Or Go start the app directly, then you don't need to load the PATH variable
+#       `ExecStart=__YNH_GO__ my_app run`
+#        You will replace __YNH_GO__ with $ynh_go
+#
+#
+# one other variable is also available
+#    - $go_path: The absolute path to Go binaries for the chosen version.
+#
+# usage: ynh_use_go
+#
+# Requires YunoHost version 3.2.2 or higher.
+ynh_use_go() {
+    go_version=$(ynh_app_setting_get --app=$app --key=go_version)
+
+    # Get the absolute path of this version of Go
+    go_path="$go_version_path/$go_version/bin"
+
+    # Allow alias to be used into bash script
+    shopt -s expand_aliases
+
+    # Create an alias for the specific version of Go and a variable as fallback
+    ynh_go="$go_path/go"
+    alias ynh_go="$ynh_go"
+
+    # Load the path of this version of Go in $PATH
+    if [[ :$PATH: != *":$go_path"* ]]; then
+        PATH="$go_path:$PATH"
+    fi
+    # Create an alias to easily load the PATH
+    ynh_go_load_path="PATH=$PATH"
+
+    # Sets the local application-specific Go version
+    pushd $install_dir
+    $goenv_install_dir/bin/goenv local $go_version
+    popd
+}
+
+# Install a specific version of Go
+#
+# ynh_install_go will install the version of Go provided as argument by using goenv.
+#
+# This helper creates a /etc/profile.d/goenv.sh that configures PATH environment for goenv
+# for every LOGIN user, hence your user must have a defined shell (as opposed to /usr/sbin/nologin)
+#
+# Don't forget to execute go-dependent command in a login environment
+# (e.g. sudo --login option)
+# When not possible (e.g. in systemd service definition), please use direct path
+# to goenv shims (e.g. $goenv_ROOT/shims/bundle)
+#
+# usage: ynh_install_go --go_version=go_version
+# | arg: -v, --go_version= - Version of go to install.
+#
+# Requires YunoHost version 3.2.2 or higher.
+ynh_install_go() {
+    # Declare an array to define the options of this helper.
+    local legacy_args=v
+    local -A args_array=([v]=go_version=)
+    local go_version
+    # Manage arguments with getopts
+    ynh_handle_getopts_args "$@"
+
+    # Load goenv path in PATH
+    local CLEAR_PATH="$goenv_install_dir/bin:$PATH"
+
+    # Remove /usr/local/bin in PATH in case of Go prior installation
+    PATH=$(echo $CLEAR_PATH | sed 's@/usr/local/bin:@@')
+
+    # Move an existing Go binary, to avoid to block goenv
+    test -x /usr/bin/go && mv /usr/bin/go /usr/bin/go_goenv
+
+    # Install or update goenv
+    goenv="$(command -v goenv $goenv_install_dir/bin/goenv | head -1)"
+    if [ -n "$goenv" ]; then
+        ynh_print_info --message="goenv already seems installed in \`$goenv'."
+        pushd "${goenv%/*/*}"
+        if git remote -v 2>/dev/null | grep "https://github.com/syndbg/goenv.git"; then
+            echo "Trying to update with git..."
+            git pull -q --tags origin master
+            cd ..
+            ynh_go_try_bash_extension
+        fi
+        popd
+    else
+        ynh_print_info --message="Installing goenv with git..."
+        mkdir -p $goenv_install_dir
+        pushd $goenv_install_dir
+        git init -q
+        git remote add -f -t master origin https://github.com/syndbg/goenv.git >/dev/null 2>&1
+        git checkout -q -b master origin/master
+        ynh_go_try_bash_extension
+        goenv=$goenv_install_dir/bin/goenv
+        popd
+    fi
+
+    goenv_latest="$(command -v "$goenv_install_dir"/plugins/*/bin/goenv-latest goenv-latest | head -1)"
+    if [ -n "$goenv_latest" ]; then
+        ynh_print_info --message="\`goenv latest' command already available in \`$goenv_latest'."
+        pushd "${goenv_latest%/*/*}"
+        if git remote -v 2>/dev/null | grep "https://github.com/momo-lab/xxenv-latest.git"; then
+            ynh_print_info --message="Trying to update xxenv-latest with git..."
+            git pull -q origin master
+        fi
+        popd
+    else
+        ynh_print_info --message="Installing xxenv-latest with git..."
+        mkdir -p "${goenv_install_dir}/plugins"
+        git clone -q https://github.com/momo-lab/xxenv-latest.git "${goenv_install_dir}/plugins/xxenv-latest"
+    fi
+
+    # Enable caching
+    mkdir -p "${goenv_install_dir}/cache"
+
+    # Create shims directory if needed
+    mkdir -p "${goenv_install_dir}/shims"
+
+    # Restore /usr/local/bin in PATH
+    PATH=$CLEAR_PATH
+
+    # And replace the old Go binary
+    test -x /usr/bin/go_goenv && mv /usr/bin/go_goenv /usr/bin/go
+
+    # Install the requested version of Go
+    local final_go_version=$(goenv latest --print $go_version)
+    ynh_print_info --message="Installation of Go-$final_go_version"
+    goenv install --skip-existing --quiet $final_go_version
+
+    # Store go_version into the config of this app
+    ynh_app_setting_set --app=$YNH_APP_INSTANCE_NAME --key=go_version --value=$final_go_version
+
+    # Cleanup Go versions
+    ynh_cleanup_go
+
+    # Set environment for Go users
+    echo "#goenv
+export GOENV_ROOT=$goenv_install_dir
+export PATH=\"$goenv_install_dir/bin:$PATH\"
+eval \"\$(goenv init -)\"
+#goenv" >/etc/profile.d/goenv.sh
+
+    # Load the environment
+    eval "$(goenv init -)"
+}
+
+# Remove the version of Go used by the app.
+#
+# This helper will also cleanup Go versions
+#
+# usage: ynh_remove_go
+ynh_remove_go() {
+    local go_version=$(ynh_app_setting_get --app=$YNH_APP_INSTANCE_NAME --key=go_version)
+
+    # Load goenv path in PATH
+    local CLEAR_PATH="$goenv_install_dir/bin:$PATH"
+
+    # Remove /usr/local/bin in PATH in case of Go prior installation
+    PATH=$(echo $CLEAR_PATH | sed 's@/usr/local/bin:@@')
+
+    # Remove the line for this app
+    ynh_app_setting_delete --app=$YNH_APP_INSTANCE_NAME --key=go_version
+
+    # Cleanup Go versions
+    ynh_cleanup_go
+}
+
+# Remove no more needed versions of Go used by the app.
+#
+# This helper will check what Go version are no more required,
+# and uninstall them
+# If no app uses Go, goenv will be also removed.
+#
+# usage: ynh_cleanup_go
+ynh_cleanup_go() {
+
+    # List required Go versions
+    local installed_apps=$(yunohost app list | grep -oP 'id: \K.*$')
+    local required_go_versions=""
+    for installed_app in $installed_apps; do
+        local installed_app_go_version=$(ynh_app_setting_get --app=$installed_app --key="go_version")
+        if [[ $installed_app_go_version ]]; then
+            required_go_versions="${installed_app_go_version}\n${required_go_versions}"
+        fi
+    done
+
+    # Remove no more needed Go versions
+    local installed_go_versions=$(goenv versions --bare --skip-aliases | grep -Ev '/')
+    for installed_go_version in $installed_go_versions; do
+        if ! $(echo ${required_go_versions} | grep "${installed_go_version}" 1>/dev/null 2>&1); then
+            ynh_print_info --message="Removing of Go-$installed_go_version"
+            $goenv_install_dir/bin/goenv uninstall --force $installed_go_version
+        fi
+    done
+
+    # If none Go version is required
+    if [[ ! $required_go_versions ]]; then
+        # Remove goenv environment configuration
+        ynh_print_info --message="Removing of goenv"
+        ynh_secure_remove --file="$goenv_install_dir"
+        ynh_secure_remove --file="/etc/profile.d/goenv.sh"
+    fi
+}
+
 #=================================================
 # FUTURE OFFICIAL HELPERS
 #=================================================