diff --git a/.installer/packages b/.installer/packages
index 922b1db..65c8b03 100644
--- a/.installer/packages
+++ b/.installer/packages
@@ -3,3 +3,13 @@ pacman-any:gst-libav,phonon-qt5-gstreamer,gst-plugins-good,qt5-quickcontrols,qt5
 pacman-any:code,vim,ufw
 pacman-laptop:brightnessctl
 aur-any:picom-git,flashfocus-git,sddm-theme-aerial-git
+
+apt-any:i3-gaps,feh,i3status,nm-tray,pasystray,xautolock,inotify-tools,xss-lock,fonts-noto-color-emoji
+apt-any:libxext-dev,libxcb1-dev,libxcb-damage0-dev,libxcb-xfixes0-dev,libxcb-shape0-dev,libxcb-render-util0-dev,libxcb-render0-dev,libxcb-randr0-dev,libxcb-composite0-dev,libxcb-image0-dev,libxcb-present-dev,libxcb-xinerama0-dev,libxcb-glx0-dev,libpixman-1-dev,libdbus-1-dev,libconfig-dev,libgl1-mesa-dev,libpcre2-dev,libpcre3-dev,libevdev-dev,uthash-dev,libev-dev,libx11-xcb-dev,meson
+apt-any:python3,python3-pip
+apt-any:libxcb-render0-dev,libffi-dev,python-dev,python-cffi
+apt-any:sddm,gstreamer1.0-libav,phonon4qt5-backend-gstreamer,gstreamer1.0-plugins-good,qml-module-qtquick-controls,qml-module-qtgraphicaleffects,qml-module-qtmultimedia,qt5-default
+apt-any:codium,vim,ufw
+apt-laptop:brightnessctl
+
+pip-any:flashfocus
diff --git a/setup_system.sh b/setup_system.sh
index 149a891..7f69fb6 100755
--- a/setup_system.sh
+++ b/setup_system.sh
@@ -92,6 +92,18 @@ function setup_arch_with_yay() {
     done
 }
 
+function install_sddm_aerial_theme() {
+    local theme_dir="/usr/share/sddm/themes/aerial"
+
+    [ -d "$theme_dir" ] && return
+
+    echo "Installing SDDM Aerial theme."
+
+    git clone https://github.com/3ximus/aerial-sddm-theme.git /tmp/aerial
+    sudo mv /tmp/aerial "$theme_dir"
+    sudo chown -R root:root "$theme_dir"
+}
+
 function configure_sddm() {
     local sddm_config_dir="/etc/sddm.conf.d"
     local theme_dir="/usr/share/sddm/themes/aerial"
@@ -135,12 +147,81 @@ function setup_arch() {
     configure_ufw || return 5
 }
 
+function setup_debian_repo_i3gaps() {
+    echo "Setting up repository for i3-gaps."
+    sudo add-apt-repository -y ppa:regolith-linux/release
+}
+
+function setup_debian_repo_vscodium() {
+    echo "Setting up repository for VSCodium."
+    wget -qO - https://gitlab.com/paulcarroty/vscodium-deb-rpm-repo/raw/master/pub.gpg |
+        gpg --dearmor |
+        sudo dd of=/usr/share/keyrings/vscodium-archive-keyring.gpg
+    echo 'deb [ signed-by=/usr/share/keyrings/vscodium-archive-keyring.gpg ] https://download.vscodium.com/debs vscodium main' |
+        sudo tee /etc/apt/sources.list.d/vscodium.list
+}
+
+function prepare_debian() {
+    setup_debian_repo_i3gaps || return 1
+    setup_debian_repo_vscodium || return 2
+}
+
+function setup_debian_with_apt() {
+    local targets=("apt-any") packages
+    is_laptop && targets+=("apt-laptop")
+
+    packages="$(get_packages "${targets[@]}")"
+    sudo apt-get update
+    # shellcheck disable=SC2086
+    sudo apt-get install $packages -y || return 1
+}
+
+function setup_debian_from_pip(){
+    local targets=("pip-any") packages
+
+    packages="$(get_packages "${targets[@]}")"
+    # shellcheck disable=SC2086
+    sudo pip3 install $packages --no-input || return 1
+}
+
+function install_picom() {
+    local tmp=/tmp/picom
+
+    echo "Installing Picom."
+
+    rm -Rf "$tmp"
+    git clone https://github.com/yshui/picom.git "$tmp" || return 1
+    cd "$tmp" || return 2
+    git submodule update --init --recursive || return 3
+    meson --buildtype=release . build || return 4
+    ninja -C build || return 5
+    sudo ninja -C build install || return 6
+    cd || return 7
+    rm -Rf "$tmp"
+}
+
+function setup_debian_from_git() {
+    install_picom || return 1
+    install_sddm_aerial_theme || return 2
+}
+
+function setup_debian() {
+    prepare_debian || return 1
+    setup_debian_with_apt || return 2
+    setup_debian_from_pip || return 3
+    setup_debian_from_git || return 4
+    configure_sddm || return 5
+    configure_ufw || return 6
+}
+
 ID_LIKE="$(grep ID_LIKE= </etc/os-release | cut -d= -f2)"
 
 echo "Setting up ${ID_LIKE^:?}-like OS."
 
 if [[ "$ID_LIKE" == "arch" ]]; then
     setup_arch
+elif [[ "$ID_LIKE" == "debian" ]]; then
+    setup_debian
 else
     echo "ERROR: Unsupported system: ID_LIKE=$ID_LIKE"
     exit 2