diff --git a/README.md b/README.md
index dbc4f3a..f687c4c 100644
--- a/README.md
+++ b/README.md
@@ -1,19 +1,20 @@
 # Debian & Ubuntu Server Setup & Hardening Script
 
+[![Debian Compatibility](https://img.shields.io/badge/Compatibility–Debian%2012%7C13-%23A81D33?style=flat&labelColor=555&logo=debian&logoColor=white)](https://www.debian.org/releases/)
+[![Ubuntu Compatibility](https://img.shields.io/badge/Compatibility–Ubuntu%2022.04%7C24.04-%23E95420?style=flat&labelColor=555&logo=ubuntu&logoColor=white)](https://ubuntu.com/download/server)
 [![Shell Script Linter](https://github.com/buildplan/du_setup/actions/workflows/lint.yml/badge.svg)](https://github.com/buildplan/du_setup/actions/workflows/lint.yml)
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
-[![Compatibility](https://img.shields.io/badge/Compatibility-Debian%2012%20%7C%20Ubuntu%2022.04%20%2F%2024.04-orange)](https://www.debian.org/)
 [![Shell](https://img.shields.io/badge/Shell-Bash%204.4%2B-green)](https://www.gnu.org/software/bash/)
 [![Type](https://img.shields.io/badge/Type-Setup%20%26%20Hardening-blue)](https://github.com/buildplan/du_setup)
 
-**Version:** v0.63
+**Version:** v0.64
 
-**Last Updated:** 2025-08-10
+**Last Updated:** 2025-08-15
 
 **Compatible With:**
 
-  * Debian 12
-  * Ubuntu 22.04, 24.04 (24.10 & 25.04 experimental)
+  * Debian 12, 13
+  * Ubuntu 20.04, 22.04, 24.04 (24.10 & 25.04 experimental)
 
 ## Overview
 
@@ -82,12 +83,12 @@ sha256sum du_setup.sh
 
 Compare the output hash to the one below. They must match exactly.
 
-`200bec06b7eb818616fc8073e4aa479c2dd3aa8c262a2e273173d31cda0286a3`
+`39dfc5716377b3468ecacd9f7a557fedca0397720c3652e5b14d8788241df789`
 
 Or echo the hash to check, it should output: `du_setup.sh: OK`
 
 ```
-echo 200bec06b7eb818616fc8073e4aa479c2dd3aa8c262a2e273173d31cda0286a3 du_setup.sh | sha256sum --check -
+echo 39dfc5716377b3468ecacd9f7a557fedca0397720c3652e5b14d8788241df789 du_setup.sh | sha256sum --check -
 ```
 
 ### 3\. Run the Script
@@ -177,7 +178,7 @@ After rebooting, verify the setup:
 
 ## Tested On
 
-  * Debian 12
+  * Debian 12, 13
   * Ubuntu 22.04, 24.04 - 24.10 & 25.04 (experimental)
   * Cloud providers: DigitalOcean, Oracle Cloud, OVH Cloud, Hetzner, Netcup
   * Backup destinations: Hetzner Storage Box (SSH, port 23), custom SSH servers
diff --git a/du_setup.sh b/du_setup.sh
index 587115f..c23a199 100644
--- a/du_setup.sh
+++ b/du_setup.sh
@@ -1,8 +1,9 @@
 #!/bin/bash
 
-# Debian 12 and Ubuntu Server Hardening Interactive Script
-# Version: 0.63 | 2025-08-10
+# Debian and Ubuntu Server Hardening Interactive Script
+# Version: 0.64 | 2025-08-15
 # Changelog:
+# - v0.64: Tested at Debian 13 to confirm it works as expected
 # - v0.63: Added ssh install in key packages
 # - v0.62: Added fix for fail2ban by creating empty ufw log file
 # - v0.61: Display Lynis suggestions in summary, hide tailscale auth key, cleanup temp files
@@ -63,7 +64,7 @@
 set -euo pipefail  # Exit on error, undefined vars, pipe failures
 
 # --- Update Configuration ---
-CURRENT_VERSION="0.63"
+CURRENT_VERSION="0.64"
 SCRIPT_URL="https://raw.githubusercontent.com/buildplan/du_setup/refs/heads/main/du_setup.sh"
 CHECKSUM_URL="${SCRIPT_URL}.sha256"
 
@@ -124,7 +125,7 @@ print_header() {
     echo -e "${CYAN}╔═════════════════════════════════════════════════════════════════╗${NC}"
     echo -e "${CYAN}║                                                                 ║${NC}"
     echo -e "${CYAN}║       DEBIAN/UBUNTU SERVER SETUP AND HARDENING SCRIPT           ║${NC}"
-    echo -e "${CYAN}║                      v0.62 | 2025-08-06                         ║${NC}"
+    echo -e "${CYAN}║                      v0.64 | 2025-08-15                         ║${NC}"
     echo -e "${CYAN}║                                                                 ║${NC}"
     echo -e "${CYAN}╚═════════════════════════════════════════════════════════════════╝${NC}"
     echo
@@ -362,11 +363,11 @@ check_system() {
     if [[ -f /etc/os-release ]]; then
         source /etc/os-release
         ID=$ID  # Populate global ID variable
-        if [[ $ID == "debian" && $VERSION_ID == "12" ]] || \
+	if [[ $ID == "debian" && $VERSION_ID =~ ^(12|13)$ ]] || \
            [[ $ID == "ubuntu" && $VERSION_ID =~ ^(20.04|22.04|24.04)$ ]]; then
             print_success "Compatible OS detected: $PRETTY_NAME"
         else
-            print_warning "Script not tested on $PRETTY_NAME. This is for Debian 12 or Ubuntu 20.04/22.04/24.04 LTS."
+            print_warning "Script not tested on $PRETTY_NAME. This is for Debian 12/13 or Ubuntu 20.04/22.04/24.04 LTS."
             if ! confirm "Continue anyway?"; then exit 1; fi
         fi
     else
@@ -660,6 +661,11 @@ setup_user() {
 
 configure_system() {
     print_section "System Configuration"
+
+    # Warn about /tmp being a RAM-backed filesystem on Debian 13+
+    print_info "Note: Debian 13 uses tmpfs for /tmp by default (stored in RAM)"
+    print_info "Large temporary files may consume system memory"
+
     mkdir -p "$BACKUP_DIR" && chmod 700 "$BACKUP_DIR"
     cp /etc/hosts "$BACKUP_DIR/hosts.backup"
     cp /etc/fstab "$BACKUP_DIR/fstab.backup"
diff --git a/du_setup.sh.sha256 b/du_setup.sh.sha256
index c1f91fa..7ceebdd 100644
--- a/du_setup.sh.sha256
+++ b/du_setup.sh.sha256
@@ -1 +1 @@
-200bec06b7eb818616fc8073e4aa479c2dd3aa8c262a2e273173d31cda0286a3  du_setup.sh
+39dfc5716377b3468ecacd9f7a557fedca0397720c3652e5b14d8788241df789  du_setup.sh