diff --git a/install_newt-msp-site_v2.sh b/install_newt-msp-site_v2.sh
index a9c65d5..6408441 100644
--- a/install_newt-msp-site_v2.sh
+++ b/install_newt-msp-site_v2.sh
@@ -1,176 +1,211 @@
 #!/bin/bash
+set -e
 
-param([string]$mode = "install")
+REPO="fosrl/newt"
+INSTALL_DIR="/opt/me-msp-newt"
+SERVICE_NAME="MAIEREDV-Managed-Site-Client"
+SYMLINK="${INSTALL_DIR}/newt_latest"
+SERVICE_FILE="/etc/systemd/system/${SERVICE_NAME}.service"
+UPDATER_SERVICE="/etc/systemd/system/newt-updater.service"
+UPDATER_TIMER="/etc/systemd/system/newt-updater.timer"
 
-# 1. Stabilität & Encoding
-[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
-[Console]::OutputEncoding = [System.Text.Encoding]::UTF8
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+RED='\033[0;31m'
+NC='\033[0m'
 
-# 2. Konfiguration
-$Repo = "fosrl/newt"
-$InstallDir = "C:\Program Files\me-msp-newt"
-$ServiceName = "MAIEREDV-Managed-Site-Client"
-$Symlink = "$InstallDir\newt_latest.exe"
-$UpdaterTaskName = "MAIEREDV-Newt-Updater"
-$GiteaUrl = "https://me-gitea.maieredv.cloud/manuel.maier/update-install-newt/raw/branch/main/install_newt-msp-site-win_v2.1.ps1"
+info()  { echo -e "${GREEN}[INFO]${NC} $1"; }
+warn()  { echo -e "${YELLOW}[WARN]${NC} $1"; }
+error() { echo -e "${RED}[ERROR]${NC} $1"; exit 1; }
 
-function Write-Log($msg, $color = "White") { 
-    Write-Host "[$(Get-Date -Format 'HH:mm:ss')] $msg" -ForegroundColor $color 
+get_latest_version() {
+  curl -fsSL "https://api.github.com/repos/${REPO}/releases/latest" | grep -Po '"tag_name": *"\K[^"]+'
 }
 
-# 3. Umgebung vorbereiten
-function Prepare-Environment {
-    if (!(Get-Command winget -ErrorAction SilentlyContinue)) {
-        Write-Log "Winget fehlt. Installiere via winget.pro..." "Cyan"
-        try {
-            Invoke-RestMethod -Uri "https://winget.pro/install.ps1" | Invoke-Expression
-            $env:Path = [System.Environment]::GetEnvironmentVariable("Path","Machine") + ";" + [System.Environment]::GetEnvironmentVariable("Path","User")
-        } catch {
-            Write-Log "FEHLER: Winget Installation fehlgeschlagen." "Red"; exit 1
-        }
-    }
+download_newt() {
+  local version="$1"
+  local arch=$(uname -m)
+  local file=""
 
-    if (!(Get-Command nssm -ErrorAction SilentlyContinue)) {
-        Write-Log "NSSM wird via Winget bereitgestellt..." "Cyan"
-        winget install nssm --silent --accept-package-agreements --accept-source-agreements | Out-Null
-        $env:Path = [System.Environment]::GetEnvironmentVariable("Path","Machine") + ";" + [System.Environment]::GetEnvironmentVariable("Path","User")
-    }
+  case "$arch" in
+    x86_64) file="newt_linux_amd64" ;;
+    aarch64) file="newt_linux_arm64" ;;
+    armv7l) file="newt_linux_arm32" ;;
+    *) error "Unsupported architecture: $arch" ;;
+  esac
+
+  local url="https://github.com/${REPO}/releases/download/${version}/${file}"
+  local target="${INSTALL_DIR}/newt_${version}"
+  mkdir -p "$INSTALL_DIR"
+
+  info "⬇️ Downloading $url …"
+  curl -fsSL "$url" -o "${target}.tmp" || error "Download failed."
+  chmod +x "${target}.tmp"
+  mv "${target}.tmp" "$target"
+  ln -sf "$target" "$SYMLINK"
+  info "✅ Installed newt ${version} at ${target}"
 }
 
-function Get-LatestVersion {
-    try {
-        $url = "https://api.github.com/repos/${Repo}/releases/latest"
-        $json = Invoke-RestMethod -Uri $url -UseBasicParsing
-        return $json.tag_name
-    } catch {
-        Write-Log "FEHLER: GitHub API nicht erreichbar." "Red"; exit 1
-    }
+setup_systemd_service() {
+  echo "🆔 Please enter the Pangolin ID: "
+  read -r PANGOLIN_ID
+  echo "🔑 Please enter the Secret: "
+  read -r PANGOLIN_SECRET
+  echo "🌐 Please enter the Endpoint (e.g. https://pangolin.domain.com): "
+  read -r PANGOLIN_ENDPOINT
+
+  cat > "$SERVICE_FILE" <<EOF
+[Unit]
+Description=Newt Client - ${SERVICE_NAME}
+After=network.target
+
+[Service]
+ExecStart=${SYMLINK} --id ${PANGOLIN_ID} --secret ${PANGOLIN_SECRET} --endpoint ${PANGOLIN_ENDPOINT}
+Restart=always
+RestartSec=5
+
+[Install]
+WantedBy=multi-user.target
+EOF
+
+  systemctl daemon-reload
+  systemctl enable "$SERVICE_NAME"
+  systemctl restart "$SERVICE_NAME"
+  info "🛠️ Systemd service ${SERVICE_NAME} has been set up and started."
 }
 
-# 4. Download & Cleanup
-function Download-Newt {
-    param($FullVersion)
-    $ArchSuffix = if ([Environment]::Is64BitOperatingSystem) { "windows_amd64.exe" } else { "windows_386.exe" }
-    $VersionOnly = $FullVersion.TrimStart('v')
-    $Url = "https://github.com/${Repo}/releases/download/${VersionOnly}/newt_${ArchSuffix}"
-    $Target = "${InstallDir}\newt_${VersionOnly}.exe"
+setup_update_timer() {
+  if [[ -f "$UPDATER_SERVICE" && -f "$UPDATER_TIMER" ]]; then
+    info "⏳ Update timer already exists – skipping."
+    return
+  fi
 
-    if (!(Test-Path $InstallDir)) { New-Item -ItemType Directory -Path $InstallDir -Force | Out-Null }
-    
-    if (!(Test-Path $Target)) {
-        Write-Log "Downloade Version $VersionOnly..." "Cyan"
-        try {
-            Start-BitsTransfer -Source $Url -Destination $Target -Priority Foreground -ErrorAction Stop
-        } catch {
-            Write-Log "BITS fehlgeschlagen. Versuche Web-Fallback..." "Yellow"
-            Invoke-WebRequest -Uri $Url -OutFile $Target -UseBasicParsing
-        }
-    }
+  info "⚙️ Creating systemd timer for daily updates …"
 
-    $Service = Get-Service $ServiceName -ErrorAction SilentlyContinue
-    $WasRunning = $Service -and $Service.Status -eq 'Running'
+  cat > "$UPDATER_SERVICE" <<EOF
+[Unit]
+Description=Automatic update for Newt installer
 
-    if ($WasRunning) {
-        Write-Log "Stoppe Dienst für Datei-Update..." "Yellow"
-        Stop-Service $ServiceName -Force
-    }
+[Service]
+Type=oneshot
+ExecStart=/bin/bash -c 'curl -fsSL https://me-gitea.maieredv.cloud/manuel.maier/update-install-newt/raw/branch/main/install_newt-msp-site_v2.sh | bash -s -- --update'
+EOF
 
-    try {
-        Copy-Item -Path $Target -Destination $Symlink -Force
-        Write-Log "newt_latest.exe aktualisiert." "Green"
-    } catch {
-        Write-Log "FEHLER: Datei blockiert." "Red"
-    }
+  cat > "$UPDATER_TIMER" <<EOF
+[Unit]
+Description=Run newt-updater.service daily
 
-    if ($WasRunning) {
-        Start-Service $ServiceName
-        Write-Log "Dienst wieder gestartet." "Green"
-    }
+[Timer]
+OnCalendar=03:00
+Persistent=true
 
-    # Cleanup: Behalte die neuesten 2 Versionen
-    $OldVersions = Get-ChildItem -Path $InstallDir -Filter "newt_*.exe" | 
-                   Where-Object { $_.Name -ne "newt_latest.exe" } | 
-                   Sort-Object LastWriteTime -Descending | 
-                   Select-Object -Skip 2
-    foreach ($file in $OldVersions) { Remove-Item $file.FullName -Force }
+[Install]
+WantedBy=timers.target
+EOF
+
+  systemctl daemon-reload
+  systemctl enable --now newt-updater.timer
+  info "✅ Update timer created (runs daily at 03:00)."
 }
 
-function Setup-Service {
-    if (!(Get-Service $ServiceName -ErrorAction SilentlyContinue)) {
-        Write-Log "--- Dienst-Konfiguration ---" "Yellow"
-        $PangolinID = Read-Host "Bitte Pangolin ID eingeben"
-        $PangolinSecret = Read-Host "Bitte Secret eingeben"
-        $PangolinEndpoint = Read-Host "Bitte Endpoint eingeben"
+mode_install() {
+  local version
+  version=$(get_latest_version)
+  version=${version#v}
+  info "📦 Latest version: $version"
 
-        $ArgList = "--id ${PangolinID} --secret ${PangolinSecret} --endpoint ${PangolinEndpoint}"
-        
-        & nssm install $ServiceName "$Symlink" $ArgList
-        & nssm set $ServiceName Description "MAIEREDV Managed Site Client"
-        & nssm set $ServiceName AppExit Default Restart
-        & nssm set $ServiceName AppRestartDelay 5000
-        
-        $LogFile = "${InstallDir}\newt_service.log"
-        & nssm set $ServiceName AppStdout "$LogFile"
-        & nssm set $ServiceName AppStderr "$LogFile"
-        & nssm set $ServiceName AppRotateFiles 1
-        & nssm set $ServiceName AppRotateOnline 1
-        & nssm set $ServiceName AppRotateBytes 10485760
-        
-        Start-Service $ServiceName
-        Write-Log "Dienst gestartet." "Green"
-    }
+  if [ -f "${INSTALL_DIR}/newt_${version}" ]; then
+    warn "⚠️ Version $version is already installed. Skipping installation."
+    warn "👉 Use '--reinstall' if you want to force a reinstall."
+    setup_update_timer
+    exit 0
+  fi
+
+  download_newt "$version"
+  setup_systemd_service
+  setup_update_timer
+  info "🚀 Installation completed!"
 }
 
-function Setup-UpdaterTask {
-    $ActionScript = "[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; `$s = (New-Object System.Net.WebClient).DownloadString('$GiteaUrl'); `$b = [scriptblock]::Create(`$s); & `$b -mode update"
-    $Action = New-ScheduledTaskAction -Execute "powershell.exe" -Argument "-NoProfile -ExecutionPolicy Bypass -Command `"$ActionScript`""
-    $Trigger = New-ScheduledTaskTrigger -Daily -At 3am
-    $Principal = New-ScheduledTaskPrincipal -UserId "SYSTEM" -LogonType ServiceAccount -RunLevel Highest
+mode_update() {
+  local version
+  version=$(get_latest_version)
+  version=${version#v}
+  info "📦 Latest version: $version"
 
-    Register-ScheduledTask -Action $Action -Trigger $Trigger -Principal $Principal -TaskName $UpdaterTaskName -Force | Out-Null
-    Write-Log "Update-Task (03:00 Uhr) registriert." "Green"
+  if [ -f "${INSTALL_DIR}/newt_${version}" ]; then
+    info "✅ Version $version is already installed. No update required."
+    setup_update_timer
+    exit 0
+  fi
+
+  download_newt "$version"
+  systemctl restart "$SERVICE_NAME"
+  setup_update_timer
+  info "🚀 Update completed!"
 }
 
-# --- Main ---
-Prepare-Environment
+mode_reinstall() {
+  local version
+  version=$(get_latest_version)
+  version=${version#v}
+  info "📦 Latest version: $version"
 
-switch ($mode) {
-    "install" {
-        $v = Get-LatestVersion
-        Download-Newt $v
-        Setup-Service
-        Setup-UpdaterTask
-        Write-Log "Installation abgeschlossen!" "Green"
-    }
-    "update" {
-        $v = Get-LatestVersion
-        $vOnly = $v.TrimStart('v')
-        $TargetVersionPath = "${InstallDir}\newt_${vOnly}.exe"
+  download_newt "$version"
+  setup_systemd_service
+  setup_update_timer
+  info "🚀 Reinstallation completed!"
+}
 
-        $NeedsUpdate = $false
-        if (!(Test-Path $TargetVersionPath)) {
-            $NeedsUpdate = $true
-        } elseif (Test-Path $Symlink) {
-            $HashLatest = (Get-FileHash $Symlink).Hash
-            $HashTarget = (Get-FileHash $TargetVersionPath).Hash
-            if ($HashLatest -ne $HashTarget) { $NeedsUpdate = $true }
-        } else { $NeedsUpdate = $true }
+mode_uninstall() {
+  warn "⚠️ Uninstalling newt and removing all systemd entries …"
 
-        if ($NeedsUpdate) {
-            Download-Newt $v
-            Write-Log "Update auf $v erledigt." "Green"
-        } else {
-            Write-Log "System aktuell ($vOnly)." "Cyan"
-            if ((Get-Service $ServiceName).Status -ne 'Running') { Start-Service $ServiceName }
-        }
-    }
-    "uninstall" {
-        Write-Log "Deinstallation..." "Yellow"
-        if (Get-Service $ServiceName -ErrorAction SilentlyContinue) {
-            Stop-Service $ServiceName -Force -ErrorAction SilentlyContinue
-            & nssm remove $ServiceName confirm
-        }
-        Unregister-ScheduledTask -TaskName $UpdaterTaskName -Confirm:$false -ErrorAction SilentlyContinue
-        Write-Log "Alles entfernt." "Green"
-    }
-}
\ No newline at end of file
+  # Stop and remove service
+  if systemctl is-active --quiet "$SERVICE_NAME"; then
+    systemctl stop "$SERVICE_NAME"
+  fi
+  systemctl disable "$SERVICE_NAME" 2>/dev/null || true
+  rm -f "$SERVICE_FILE"
+
+  # Remove updater
+  if systemctl is-active --quiet newt-updater.timer; then
+    systemctl stop newt-updater.timer
+  fi
+  systemctl disable newt-updater.timer 2>/dev/null || true
+  rm -f "$UPDATER_SERVICE" "$UPDATER_TIMER"
+
+  systemctl daemon-reload
+
+  # Delete installation dir (ask first)
+  if [ -d "$INSTALL_DIR" ]; then
+    read -p "❓ Do you want to remove ${INSTALL_DIR} and all versions? (y/N): " yn
+    case $yn in
+      [Yy]*) rm -rf "$INSTALL_DIR"; info "📂 ${INSTALL_DIR} was removed." ;;
+      *) warn "📂 ${INSTALL_DIR} was NOT removed." ;;
+    esac
+  fi
+
+  info "🧹 Uninstallation completed!"
+}
+
+main() {
+  case "$1" in
+    --install|"")
+      mode_install
+      ;;
+    --update)
+      mode_update
+      ;;
+    --reinstall)
+      mode_reinstall
+      ;;
+    --uninstall)
+      mode_uninstall
+      ;;
+    *)
+      error "❌ Unknown parameter: $1 (use --install, --update, --reinstall or --uninstall)"
+      ;;
+  esac
+}
+
+main "$@"