diff --git a/install.sh b/install.sh
index 845f10a..6ce0105 100755
--- a/install.sh
+++ b/install.sh
@@ -1,127 +1,192 @@
-#!/bin/bash
+#!/usr/bin/env bash
+set -Eeuo pipefail
 
-# Color codes for output formatting
-GREEN='\033[0;32m'
-YELLOW='\033[1;33m'
-RED='\033[0;31m'
-NC='\033[0m' # No Color
-
-echo -e "${GREEN}=====================================================${NC}"
-echo -e "${GREEN}      АО КМУ «Гидромонтаж» - Адресная книга          ${NC}"
-echo -e "${GREEN}            Проверка окружения и безопасности        ${NC}"
-echo -e "${GREEN}=====================================================${NC}"
-
-# 1. Check if folder already exists and is not empty
+APP_NAME="corp-address-book"
+CONTAINER_NAME="corporate-address-book"
 INSTALL_DIR="/opt/corp-address-book"
-if [ -d "$INSTALL_DIR" ] && [ "$(ls -A "$INSTALL_DIR" 2>/dev/null)" ]; then
-  echo -e "${RED}[X] ОШИБКА: Директория установки $INSTALL_DIR уже существует и не пуста!${NC}"
-  echo -e "${RED}    Во избежание перезаписи чужих файлов установка остановлена.${NC}"
+REPO_URL="https://git.h0melab.ru/fabritsky/corp-address-book.git"
+HOST_PORT="8180"
+CONTAINER_PORT="3000"
+IMAGE_NAME="corp-address-book:latest"
+
+log() {
+  printf '\n[%s] %s\n' "$(date +'%H:%M:%S')" "$*"
+}
+
+die() {
+  printf '\nERROR: %s\n' "$*" >&2
   exit 1
-fi
+}
 
-# 2. Check if port 8180 is busy on the server
-if command -v lsof >/dev/null 2>&1; then
-  if lsof -i :8180 >/dev/null 2>&1; then
-    echo -e "${RED}[X] ОШИБКА: Порт 8180 уже занят другим процессом!${NC}"
-    lsof -i :8180
-    exit 1
+need_root_or_sudo() {
+  if [ "${EUID:-$(id -u)}" -ne 0 ] && ! command -v sudo >/dev/null 2>&1; then
+    die "Run as root or install sudo first."
   fi
-elif command -v netstat >/dev/null 2>&1; then
-  if netstat -tuln | grep -q ":8180 "; then
-    echo -e "${RED}[X] ОШИБКА: Порт 8180 уже занят другим процессом!${NC}"
-    exit 1
+}
+
+as_root() {
+  if [ "${EUID:-$(id -u)}" -eq 0 ]; then
+    "$@"
+  else
+    sudo "$@"
   fi
-fi
+}
 
-# 3. Check if docker container with name 'corporate-address-book' already exists
-if command -v docker >/dev/null 2>&1; then
-  if docker ps -a --format '{{.Names}}' | grep -Eq "^corporate-address-book$"; then
-    echo -e "${RED}[X] ОШИБКА: Контейнер с именем 'corporate-address-book' уже существует!${NC}"
-    echo -e "${RED}    Пожалуйста, удалите или переименуйте существующий контейнер перед установкой.${NC}"
-    exit 1
+install_base_packages() {
+  log "Installing required base packages"
+  as_root apt-get update
+  as_root DEBIAN_FRONTEND=noninteractive apt-get install -y \
+    ca-certificates \
+    curl \
+    git \
+    gnupg
+}
+
+install_docker_if_needed() {
+  if command -v docker >/dev/null 2>&1; then
+    log "Docker is already installed"
+  else
+    log "Installing Docker Engine from the official Docker repository"
+    as_root install -m 0755 -d /etc/apt/keyrings
+    curl -fsSL https://download.docker.com/linux/ubuntu/gpg | as_root gpg --dearmor -o /etc/apt/keyrings/docker.gpg
+    as_root chmod a+r /etc/apt/keyrings/docker.gpg
+
+    . /etc/os-release
+    arch="$(dpkg --print-architecture)"
+    codename="${VERSION_CODENAME:-}"
+    [ -n "$codename" ] || die "Cannot determine Ubuntu codename."
+
+    printf 'deb [arch=%s signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu %s stable\n' "$arch" "$codename" |
+      as_root tee /etc/apt/sources.list.d/docker.list >/dev/null
+
+    as_root apt-get update
+    as_root DEBIAN_FRONTEND=noninteractive apt-get install -y docker-ce docker-ce-cli containerd.io
   fi
-fi
 
-echo -e "${GREEN}[✓] Проверка пройдена. Конфликтов не обнаружено.${NC}"
-echo -e "${YELLOW}[i] Начинаем установку...${NC}"
+  if ! docker compose version >/dev/null 2>&1; then
+    log "Installing Docker Compose plugin"
+    as_root apt-get update
+    as_root DEBIAN_FRONTEND=noninteractive apt-get install -y docker-compose-plugin
+  else
+    log "Docker Compose plugin is already installed"
+  fi
 
-# Verify if Docker is installed
-if ! [ -x "$(command -v docker)" ]; then
-  echo -e "${YELLOW}[!] Docker не установлен. Устанавливаем Docker...${NC}"
-  sudo apt-get update
-  sudo apt-get install -y apt-transport-https ca-certificates curl software-properties-common
-  curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
-  sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
-  sudo apt-get update
-  sudo apt-get install -y docker-ce
-  sudo systemctl start docker
-  sudo systemctl enable docker
-  echo -e "${GREEN}[✓] Docker успешно установлен!${NC}"
-else
-  echo -e "${GREEN}[✓] Docker обнаружен.${NC}"
-fi
+  as_root systemctl enable --now docker
+}
 
-# Verify if Docker Compose is installed
-if ! docker compose version >/dev/null 2>&1 && ! [ -x "$(command -v docker-compose)" ]; then
-  echo -e "${YELLOW}[!] Docker Compose не установлен. Устанавливаем...${NC}"
-  sudo curl -L "https://github.com/docker/compose/releases/latest/download/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
-  sudo chmod +x /usr/local/bin/docker-compose
-  echo -e "${GREEN}[✓] Docker Compose установлен!${NC}"
-else
-  echo -e "${GREEN}[✓] Docker Compose обнаружен.${NC}"
-fi
+prepare_repo() {
+  log "Preparing repository in ${INSTALL_DIR}"
+  as_root mkdir -p "$INSTALL_DIR"
 
-# Create directory structure
-sudo mkdir -p "$INSTALL_DIR"
-sudo cp -r . "$INSTALL_DIR"
-cd "$INSTALL_DIR"
+  if [ -d "${INSTALL_DIR}/.git" ]; then
+    as_root git -C "$INSTALL_DIR" remote set-url origin "$REPO_URL"
+    as_root git -C "$INSTALL_DIR" fetch --prune origin
+    as_root git -C "$INSTALL_DIR" pull --ff-only origin main
+  elif [ -z "$(as_root find "$INSTALL_DIR" -mindepth 1 -maxdepth 1 -print -quit)" ]; then
+    as_root git clone "$REPO_URL" "$INSTALL_DIR"
+  else
+    die "${INSTALL_DIR} exists and is not a git repository. Move it aside or initialize it manually."
+  fi
+}
 
-# Create .env file with secure settings if it doesn't exist
-if [ ! -f .env ]; then
-  echo -e "${YELLOW}[!] Файл настроек .env отсутствует. Создаем новый...${NC}"
-  
-  # Generate random admin password and JWT secret
-  RANDOM_PASS=$(openssl rand -base64 12 | tr -d '/+=')
-  JWT_SEC=$(openssl rand -base64 32 | tr -d '/+=')
+prepare_env_and_data() {
+  log "Preparing persistent data and environment"
+  as_root mkdir -p "${INSTALL_DIR}/data"
 
-  cat <<EOT > .env
-# Настройки учетных данных администратора
+  if [ ! -f "${INSTALL_DIR}/.env" ]; then
+    jwt_secret="$(openssl rand -hex 32 2>/dev/null || date +%s%N)"
+    admin_password="$(openssl rand -base64 24 2>/dev/null | tr -d '\n' || date +%s%N)"
+    as_root tee "${INSTALL_DIR}/.env" >/dev/null <<EOF_ENV
+# Created by install.sh. Keep this file private and do not commit it.
+# Change ADMIN_PASSWORD after first login.
+PORT=${CONTAINER_PORT}
+NODE_ENV=production
+DATABASE_PATH=/app/data/database.db
 ADMIN_USERNAME=admin
-ADMIN_PASSWORD=$RANDOM_PASS
+ADMIN_PASSWORD=${admin_password}
+JWT_SECRET=${jwt_secret}
+EOF_ENV
+    as_root chmod 600 "${INSTALL_DIR}/.env"
+    log "Created ${INSTALL_DIR}/.env with generated credentials. Values were not printed."
+  else
+    log "Existing ${INSTALL_DIR}/.env found; keeping it unchanged"
+  fi
 
-# Секретный ключ для JWT токенов
-JWT_SECRET=$JWT_SEC
-EOT
-  echo -e "${GREEN}[✓] Файл .env успешно сгенерирован.${NC}"
-else
-  echo -e "${GREEN}[✓] Обнаружен существующий файл настроек .env.${NC}"
-fi
+  if [ ! -f "${INSTALL_DIR}/.env.example" ]; then
+    as_root tee "${INSTALL_DIR}/.env.example" >/dev/null <<EOF_EXAMPLE
+PORT=${CONTAINER_PORT}
+NODE_ENV=production
+DATABASE_PATH=/app/data/database.db
+ADMIN_USERNAME=admin
+ADMIN_PASSWORD=change-me-before-use
+JWT_SECRET=replace-with-a-long-random-secret
+EOF_EXAMPLE
+  fi
+}
 
-# Load environment variables
-export $(grep -v '^#' .env | xargs)
+build_image() {
+  log "Building Docker image ${IMAGE_NAME}"
+  as_root docker build -t "$IMAGE_NAME" "$INSTALL_DIR"
+}
 
-# Start docker compose containers with project name
-echo -e "${YELLOW}[i] Сборка и запуск контейнеров в фоновом режиме...${NC}"
-if docker compose version >/dev/null 2>&1; then
-  sudo docker compose -p corp-address-book up -d --build
-else
-  sudo docker-compose -p corp-address-book up -d --build
-fi
+replace_container() {
+  log "Starting ${CONTAINER_NAME} on port ${HOST_PORT}"
 
-if [ $? -eq 0 ]; then
-  echo -e "${GREEN}=====================================================${NC}"
-  echo -e "${GREEN}[✓] УСТАНОВКА ЗАВЕРШЕНА УСПЕШНО!${NC}"
-  echo -e "${GREEN}=====================================================${NC}"
-  echo -e "Сайт адресной книги доступен по адресу:"
-  echo -e "🔗 ${YELLOW}http://192.168.1.250:8180/${NC} (или по IP-адресу вашего сервера на порту 8180)"
-  echo -e ""
-  echo -e "Данные для входа в панель администратора:"
-  echo -e "Логин:  ${YELLOW}$ADMIN_USERNAME${NC}"
-  echo -e "Пароль: ${YELLOW}$ADMIN_PASSWORD${NC}"
-  echo -e ""
-  echo -e "${RED}ВАЖНО: Сохраните эти учетные данные! Вы можете изменить их в файле .env${NC}"
-  echo -e "====================================================="
-else
-  echo -e "${RED}[X] Произошла ошибка во время сборки или запуска контейнеров.${NC}"
-  exit 1
-fi
+  old_name=""
+  if as_root docker container inspect "$CONTAINER_NAME" >/dev/null 2>&1; then
+    old_name="${CONTAINER_NAME}-old-$(date +%Y%m%d-%H%M%S)"
+    as_root docker stop "$CONTAINER_NAME"
+    as_root docker rename "$CONTAINER_NAME" "$old_name"
+    log "Previous container renamed to ${old_name}"
+  fi
+
+  if ! as_root docker run -d \
+    --name "$CONTAINER_NAME" \
+    --restart unless-stopped \
+    --env-file "${INSTALL_DIR}/.env" \
+    -p "${HOST_PORT}:${CONTAINER_PORT}" \
+    -v "${INSTALL_DIR}/data:/app/data" \
+    "$IMAGE_NAME"; then
+    if [ -n "$old_name" ]; then
+      log "New container failed to start; attempting rollback to ${old_name}"
+      as_root docker start "$old_name" || true
+    fi
+    die "Failed to start ${CONTAINER_NAME}."
+  fi
+
+  sleep 5
+  if ! curl -fsSI "http://127.0.0.1:${HOST_PORT}/" >/dev/null; then
+    as_root docker logs --tail=80 "$CONTAINER_NAME" || true
+    if [ -n "$old_name" ]; then
+      log "Health check failed; attempting rollback to ${old_name}"
+      as_root docker stop "$CONTAINER_NAME" || true
+      as_root docker rename "$CONTAINER_NAME" "${CONTAINER_NAME}-failed-$(date +%Y%m%d-%H%M%S)" || true
+      as_root docker start "$old_name" || true
+    fi
+    die "Health check failed on http://127.0.0.1:${HOST_PORT}/."
+  fi
+}
+
+print_result() {
+  server_ip="$(hostname -I 2>/dev/null | awk '{print $1}')"
+  if [ -z "${server_ip:-}" ]; then
+    server_ip="SERVER_IP"
+  fi
+
+  log "Installation completed"
+  printf 'Local check: http://127.0.0.1:%s/\n' "$HOST_PORT"
+  printf 'Open: http://%s:%s/\n' "$server_ip" "$HOST_PORT"
+}
+
+main() {
+  need_root_or_sudo
+  install_base_packages
+  install_docker_if_needed
+  prepare_repo
+  prepare_env_and_data
+  build_image
+  replace_container
+  print_result
+}
+
+main "$@"