diff --git a/install.sh b/install.sh
index 73f94b6..afd7e3d 100755
--- a/install.sh
+++ b/install.sh
@@ -266,14 +266,14 @@ print_header "Installing System Dependencies"
 if command -v apt-get &> /dev/null; then
     # Debian/Ubuntu/Raspberry Pi OS
     print_info "Detected Debian/Ubuntu-based system"
-    echo "Installing: python3-pip python3-gi python3-dbus python3-cairo bluez libcap2-bin"
+    echo "Installing: python3-pip python3-gi python3-dbus python3-cairo bluez libcap2-bin libffi-dev"
     # Use sudo only if not running as root
     if [ "$EUID" -eq 0 ]; then
         apt-get update
-        apt-get install -y python3-pip python3-gi python3-dbus python3-cairo bluez libcap2-bin
+        apt-get install -y python3-pip python3-gi python3-dbus python3-cairo bluez libcap2-bin libffi-dev
     else
         sudo apt-get update
-        sudo apt-get install -y python3-pip python3-gi python3-dbus python3-cairo bluez libcap2-bin
+        sudo apt-get install -y python3-pip python3-gi python3-dbus python3-cairo bluez libcap2-bin libffi-dev
     fi
     print_success "System dependencies installed (using pre-compiled system packages)"
 elif command -v pacman &> /dev/null; then
diff --git a/tests/test_installer.sh b/tests/test_installer.sh
index a361145..4030a48 100755
--- a/tests/test_installer.sh
+++ b/tests/test_installer.sh
@@ -205,7 +205,7 @@ echo "Installation summary:"
 echo "  • install.sh is fully self-contained (handles all prerequisites)"
 echo "  • Reticulum Network Stack: installed via pip"
 if [ "$OS_TYPE" = "debian" ]; then
-    echo "  • System packages: python3, python3-pip, git, python3-gi, python3-dbus, python3-cairo, bluez"
+    echo "  • System packages: python3, python3-pip, git, python3-gi, python3-dbus, python3-cairo, bluez, libffi-dev"
     echo "  • Pip packages: rns, bleak, bluezero"
     echo "  • Install method: System packages (no compilation)"
     echo "  • Installation time: < 1 minute"