diff --git a/README.md b/README.md
index 6e5f440..b4437df 100755
--- a/README.md
+++ b/README.md
@@ -365,15 +365,17 @@ Key Files Explained:
 
 This is the recommended method for production deployment. The `deploy.sh` script automates the entire deployment process.
 
-**Prerequisites:**
+**Prerequisites (ALL REQUIRED):**
 - Ubuntu/Debian or CentOS/RHEL server
 - Apache 2.4+ or Nginx
 - PHP 7.4+ with PHP-FPM
-- Python 3.8+
-- Composer
-- FFmpeg
+- Python 3.8+ with pip and venv
+- **Composer** (PHP dependency manager) - deploy script will fail without it
+- **FFmpeg** (audio processing) - transcription will fail without it
 - Root/sudo access
 
+**The deploy script checks for these and will exit with an error if any are missing.**
+
 ### Initial Setup
 
 **Step 1: Install system dependencies**
@@ -551,6 +553,48 @@ Production Server:
 
 ### Troubleshooting Deployment
 
+**"Failed to open vendor/autoload.php" error:**
+```
+PHP Fatal error: Failed opening required '/var/www/html/voice2txt/vendor/autoload.php'
+```
+
+This means Composer dependencies are missing. Fix:
+```bash
+# 1. Check if Composer is installed
+composer --version
+
+# If not installed:
+curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
+
+# 2. Install dependencies in backend
+cd /opt/voice2text
+sudo composer install --no-dev --optimize-autoloader
+
+# 3. Verify vendor/ was created
+ls -la vendor/autoload.php
+
+# 4. Copy to frontend
+sudo cp -r vendor /var/www/html/voice2txt/
+
+# 5. Fix permissions
+sudo chown -R www-data:www-data /var/www/html/voice2txt/vendor
+
+# 6. Verify frontend has it
+ls -la /var/www/html/voice2txt/vendor/autoload.php
+
+# 7. Restart Apache
+sudo systemctl restart apache2
+```
+
+**Deploy script fails with "Composer not found":**
+The deploy script now REQUIRES Composer to be installed. Install it:
+```bash
+curl -sS https://getcomposer.org/installer | php
+sudo mv composer.phar /usr/local/bin/composer
+sudo chmod +x /usr/local/bin/composer
+composer --version
+```
+
 **Service won't start:**
 ```bash
 # Check service logs
diff --git a/deploy.sh b/deploy.sh
index c37a56d..09cb7e8 100755
--- a/deploy.sh
+++ b/deploy.sh
@@ -129,6 +129,33 @@ print_success "Backend directory exists: $BACKEND_DIR"
 # Change to backend directory
 cd "$BACKEND_DIR"
 
+# Check for required system dependencies
+print_header "Checking Required Dependencies"
+
+# Check Python (REQUIRED)
+if ! command -v python3 &> /dev/null; then
+    print_error "Python 3 is not installed (REQUIRED)"
+    print_info "Install: sudo apt install python3 python3-venv python3-pip"
+    exit 1
+fi
+print_success "Python 3 found: $(python3 --version)"
+
+# Check Composer (REQUIRED for PHP dependencies)
+if ! command -v composer &> /dev/null; then
+    print_error "Composer is not installed (REQUIRED)"
+    print_info "Install: curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer"
+    exit 1
+fi
+print_success "Composer found: $(composer --version | head -n 1)"
+
+# Check FFmpeg (REQUIRED for audio processing)
+if ! command -v ffmpeg &> /dev/null; then
+    print_error "FFmpeg is not installed (REQUIRED)"
+    print_info "Install: sudo apt install ffmpeg"
+    exit 1
+fi
+print_success "FFmpeg found: $(ffmpeg -version | head -n 1 | cut -d' ' -f3)"
+
 # Detect if this is first deployment
 FIRST_DEPLOY=false
 if [ ! -f "$SERVICE_PATH" ]; then
@@ -197,15 +224,25 @@ if [ "$FRONTEND_ONLY" != true ]; then
     run_command venv/bin/pip install -r requirements.txt
     print_success "Python dependencies installed"
 
-    # Install/update Composer dependencies
-    if command -v composer &> /dev/null; then
-        print_info "Installing PHP dependencies (Composer)..."
-        run_command composer install --no-dev --optimize-autoloader
-        print_success "Composer dependencies installed"
-    else
-        print_warning "Composer not found - skipping PHP dependencies"
+    # Install/update Composer dependencies (REQUIRED)
+    print_info "Installing PHP dependencies (Composer)..."
+    run_command composer install --no-dev --optimize-autoloader
+
+    # VERIFY vendor/ directory was created
+    if [ ! -d "vendor" ]; then
+        print_error "Composer dependencies failed to install - vendor/ directory missing!"
+        print_info "Try running: composer install --verbose"
+        exit 1
     fi
 
+    if [ ! -f "vendor/autoload.php" ]; then
+        print_error "Composer autoload.php is missing!"
+        print_info "This indicates a broken Composer installation"
+        exit 1
+    fi
+
+    print_success "Composer dependencies installed and verified"
+
     # Create outputs directory if it doesn't exist
     if [ ! -d "outputs" ]; then
         print_info "Creating outputs directory..."
@@ -308,12 +345,24 @@ if [ "$BACKEND_ONLY" != true ]; then
         run_command cp "$BACKEND_DIR/V2T.svg" "$FRONTEND_DIR/"
     fi
 
-    # Composer vendor directory
-    if [ -d "$BACKEND_DIR/vendor" ]; then
-        print_info "Copying Composer dependencies..."
-        run_command cp -r "$BACKEND_DIR/vendor" "$FRONTEND_DIR/"
+    # Composer vendor directory (REQUIRED)
+    if [ ! -d "$BACKEND_DIR/vendor" ]; then
+        print_error "vendor/ directory not found in backend!"
+        print_info "This should have been created during backend deployment"
+        exit 1
     fi
 
+    print_info "Copying Composer dependencies..."
+    run_command cp -r "$BACKEND_DIR/vendor" "$FRONTEND_DIR/"
+
+    # VERIFY vendor/ was copied successfully
+    if [ ! -f "$FRONTEND_DIR/vendor/autoload.php" ]; then
+        print_error "Failed to copy vendor/ to frontend!"
+        print_info "Check permissions and disk space"
+        exit 1
+    fi
+
+    print_success "Composer dependencies copied and verified"
     print_success "Frontend files copied"
 
     # Handle .env file for frontend