diff --git a/docker-arm/home-manager/home.nix b/docker-arm/home-manager/home.nix
index c472688..a243c34 100644
--- a/docker-arm/home-manager/home.nix
+++ b/docker-arm/home-manager/home.nix
@@ -26,7 +26,10 @@ in
   };
 
   programs = util.programs // {
-    bash.enable = true; # Necessary for aliases and Starship to work.
+    bash = {
+      enable = true; # Necessary for aliases and Starship to work.
+      initExtra = util.shellInit;
+    };
   };
 
   assertions = util.assertions;
diff --git a/docker-x86/home-manager/home.nix b/docker-x86/home-manager/home.nix
index f46603f..8e1357e 100644
--- a/docker-x86/home-manager/home.nix
+++ b/docker-x86/home-manager/home.nix
@@ -26,7 +26,10 @@ in
   };
 
   programs = util.programs // {
-    bash.enable = true; # Necessary for aliases and Starship to work.
+    bash = {
+      enable = true; # Necessary for aliases and Starship to work.
+      initExtra = util.shellInit;
+    };
   };
 
   assertions = util.assertions;
diff --git a/macos/home-manager/home.nix b/macos/home-manager/home.nix
index ba19194..3b5271e 100644
--- a/macos/home-manager/home.nix
+++ b/macos/home-manager/home.nix
@@ -69,7 +69,10 @@ in
   };
 
   programs = util.programs // {
-    zsh.enable = true; # Necessary for aliases and Starship to work.
+    zsh = {
+      enable = true; # Necessary for aliases and Starship to work.
+      initContent = util.shellInit;
+    };
   };
 
   assertions = util.assertions;
diff --git a/nixos/home-manager/home.nix b/nixos/home-manager/home.nix
index e95bf86..01bf3c3 100644
--- a/nixos/home-manager/home.nix
+++ b/nixos/home-manager/home.nix
@@ -49,7 +49,10 @@ in
   };
 
   programs = util.programs // {
-    bash.enable = true; # Necessary for aliases and Starship to work.
+    bash = {
+      enable = true; # Necessary for aliases and Starship to work.
+      initExtra = util.shellInit;
+    };
 
     firefox = {
       enable = true;
diff --git a/tart/home-manager/home.nix b/tart/home-manager/home.nix
index 75f4765..ca884a9 100644
--- a/tart/home-manager/home.nix
+++ b/tart/home-manager/home.nix
@@ -26,7 +26,10 @@ in
   };
 
   programs = util.programs // {
-    zsh.enable = true; # Necessary for aliases and Starship to work.
+    zsh = {
+      enable = true; # Necessary for aliases and Starship to work.
+      initContent = util.shellInit;
+    };
   };
 
   assertions = util.assertions;
diff --git a/util.nix b/util.nix
index 96c86a8..47ffe83 100644
--- a/util.nix
+++ b/util.nix
@@ -53,6 +53,23 @@ rec {
     ".gitconfig" = symlink ".gitconfig";
   };
 
+  shellInit = ''
+    ghcd() {
+      local regex='^((https://)?github\.com/)?([A-Za-z0-9._-]+/[A-Za-z0-9._-]+)'
+      local repo
+      repo=$(printf '%s' "''${1-}" | sed -nE "s|''${regex}.*|\3|p")
+      if [ -z "$repo" ]; then
+        printf 'must match this regex: %s\n' "$regex" >&2
+        return 1
+      fi
+      local dir="$HOME/github/$repo"
+      if [ ! -e "$dir" ]; then
+        git clone --recurse-submodules "https://github.com/$repo.git" "$dir" || return $?
+      fi
+      cd "$dir"
+    }
+  '';
+
   programs = {
     eza.enable = true;