diff --git a/packages/packages.sh b/packages/packages.sh
index 4a778d3..c58ea96 100755
--- a/packages/packages.sh
+++ b/packages/packages.sh
@@ -162,6 +162,49 @@ if has_tags pm:pipx; then
 		thefuck
 fi
 
+# change git user settings
+
+set_git_config_if_unset() {
+	local name
+	local value
+	name="$1"
+	value="$2"
+	if ! git config --global --get "$1" >/dev/null; then
+		echo "Configuring global git setting: $1 = $2"
+		git config --global "$1" "$2"
+	fi
+}
+
+clear_git_config_if_pointing_nowhere() {
+	local name
+	name="$1"
+	if git config --global --get "$1" >/dev/null && ! command -v $(git config --global --get "$1") >/dev/null; then
+		echo "Resetting global git setting since it no longer points anywhere useful: $1"
+		git config --global --unset "$1"
+	fi
+}
+
+set_git_config_if_unset alias.change-commits '!f() { VAR=$1; OLD=$2; NEW=$3; shift 3; git filter-branch --env-filter \"if [[ \\\"$`echo $VAR`\\\" = '"'"'$OLD'"'"' ]]; then export $VAR='"'"'$NEW'"'"'; fi\" $@; }; f'
+set_git_config_if_unset alias.glog 'log --all --pretty="format:%d %Cgreen%h%Creset %an - %s" --graph'
+set_git_config_if_unset commit.gpgsign true
+set_git_config_if_unset core.autocrlf input
+set_git_config_if_unset core.editor "$EDITOR"
+set_git_config_if_unset init.defaultBranch main
+set_git_config_if_unset pull.rebase false
+set_git_config_if_unset tag.gpgsign true
+set_git_config_if_unset user.email "icedream@icedream.pw"
+set_git_config_if_unset user.name "Carl Kittelberger"
+#set_git_config_if_unset user.signingkey B5108C5A158A6608AD3361DA1573F6D8EFE4D0CF
+set_git_config_if_unset user.signingkey 04ADEF85EA6AEC6F75941E84468BBEEBB9EC6AEA
+
+# set up kdiff3 as mergetool if it is installed
+clear_git_config_if_pointing_nowhere merge.tool
+for bin in kdiff3 meld p4merge vimdiff; do
+	if command -v "$bin" >/dev/null; then
+		set_git_config_if_unset merge.tool "$bin"
+	fi
+done
+
 # change default terminal to urxvt
 
 if has_tags desktop; then