diff --git a/Makefile b/Makefile
index fefd5cb..02566bc 100644
--- a/Makefile
+++ b/Makefile
@@ -39,7 +39,7 @@ help:
 
 # Setup commands
 check-deps:
-	@sh scripts/check_deps.sh
+	@sudo sh scripts/check_deps.sh
 
 setup: check-deps
 	@echo "Setting up Personal Internet Cell..."
diff --git a/scripts/check_deps.sh b/scripts/check_deps.sh
index 241046c..3fbffd3 100755
--- a/scripts/check_deps.sh
+++ b/scripts/check_deps.sh
@@ -1,48 +1,56 @@
 #!/bin/sh
-# Install Python dependencies needed by setup_cell.py
+# Install all host dependencies required by Personal Internet Cell.
+# Uses apt-get (Debian/Ubuntu). Must be run with sudo or as root.
 set -e
 
-echo "Checking system dependencies..."
+APT_UPDATED=0
 
-# Ensure python3 is available
-if ! command -v python3 >/dev/null 2>&1; then
-    echo "Installing python3..."
-    sudo apt-get install -y python3 || { echo "ERROR: python3 not found and could not install it."; exit 1; }
+apt_install() {
+    PKG="$1"
+    if ! dpkg -s "$PKG" >/dev/null 2>&1; then
+        echo "  Installing $PKG..."
+        if [ "$APT_UPDATED" = "0" ]; then
+            apt-get update -qq
+            APT_UPDATED=1
+        fi
+        apt-get install -y -qq "$PKG"
+    else
+        echo "  [ok] $PKG"
+    fi
+}
+
+echo "=== Checking system dependencies ==="
+
+# Core tools
+apt_install git
+apt_install curl
+apt_install openssl
+apt_install python3
+apt_install python3-cryptography
+
+# Docker
+if ! command -v docker >/dev/null 2>&1; then
+    echo "  Installing docker..."
+    if [ "$APT_UPDATED" = "0" ]; then
+        apt-get update -qq
+        APT_UPDATED=1
+    fi
+    apt-get install -y -qq docker.io
+fi
+echo "  [ok] docker"
+
+# Docker Compose (v2 plugin preferred, v1 fallback)
+if ! docker compose version >/dev/null 2>&1 && ! command -v docker-compose >/dev/null 2>&1; then
+    echo "  Installing docker-compose..."
+    apt-get install -y -qq docker-compose
+fi
+echo "  [ok] docker-compose"
+
+# Ensure current user is in docker group
+if ! id | grep -q '(docker)'; then
+    echo "  Adding $(id -un) to docker group..."
+    usermod -aG docker "$(id -un)"
+    echo "  NOTE: Log out and back in (or run 'newgrp docker') for docker group to take effect."
 fi
 
-# Check if cryptography is already importable
-if python3 -c "import cryptography" 2>/dev/null; then
-    echo "Dependencies OK."
-    exit 0
-fi
-
-echo "Installing python3-cryptography..."
-
-# 1. Try apt (works if sudo is passwordless or interactive TTY is available)
-if sudo -n apt-get install -y python3-cryptography 2>/dev/null; then
-    echo "Dependencies OK."
-    exit 0
-fi
-
-# 2. Try pip (module form, covers both pip3 and python3 -m pip)
-if python3 -m pip install --user cryptography 2>/dev/null; then
-    echo "Dependencies OK."
-    exit 0
-fi
-
-# 3. Bootstrap pip via get-pip.py, then install
-if command -v curl >/dev/null 2>&1; then
-    curl -sSL https://bootstrap.pypa.io/get-pip.py -o /tmp/get-pip.py 2>/dev/null \
-        && python3 /tmp/get-pip.py --user -q 2>/dev/null \
-        && python3 -m pip install --user cryptography 2>/dev/null \
-        && { echo "Dependencies OK."; exit 0; }
-fi
-
-# 4. No automated path worked — ask the user to install manually
-echo ""
-echo "ERROR: Could not install python3-cryptography automatically."
-echo "Please run the following command and then retry:"
-echo ""
-echo "  sudo apt-get install -y python3-cryptography"
-echo ""
-exit 1
+echo "=== All dependencies OK ==="