diff --git a/run_onchange_before_install_main_deps.sh.tmpl b/run_onchange_before_install_main_deps.sh.tmpl
index d4bdb6d..e6a3e5e 100644
--- a/run_onchange_before_install_main_deps.sh.tmpl
+++ b/run_onchange_before_install_main_deps.sh.tmpl
@@ -43,16 +43,16 @@ $Green##########################################################################
 ###############################################################################$NC"
 
 {{ if eq .chezmoi.os "darwin" -}}
-  brew install -q $BASE_PACKAGES python
+  brew install -q $BASE_PACKAGES python difftastic
 
 {{ else if eq .chezmoi.osRelease.id "fedora" -}}
-    sudo dnf install $BASE_PACKAGES kitty-terminfo util-linux-user python3-pip -y
+    sudo dnf install $BASE_PACKAGES difftastic kitty-terminfo util-linux-user python3-pip -y
 
 {{ else if eq .chezmoi.osRelease.id "debian" "ubuntu" -}}
     sudo apt install $BASE_PACKAGES kitty-terminfo python3-pip -y
 
 {{ else if eq .chezmoi.osRelease.id "arch" -}}
-    sudo pacman -Sy --noconfirm $BASE_PACKAGES kitty-terminfo python3-pip
+    sudo pacman -Sy --noconfirm $BASE_PACKAGES difftastic kitty-terminfo python3-pip
 
 {{ end -}}