diff --git a/README.md b/README.md
index f29a6da..3b65aab 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,11 @@ The file format is as follows:
 
 ```
 KEY COMPLETION :CMD
+KEY COMPLETION |CMD
 KEY COMPLETION CMD
 ```
 
-If `CMD` contains a `:` prefix, the command will be prefixed with `git`.
+If `CMD` contains a colon (`:`) prefix, the command will be prefixed with `git`. If
+prefixed with a pipe (`|`), the command will be sent to `eval` (needed for
+certain features like subshells). Commands without either prefix will be
+executed normally.
diff --git a/bash_completion b/bash_completion
index a432cca..1575ae1 100644
--- a/bash_completion
+++ b/bash_completion
@@ -18,6 +18,9 @@
 
 __git-short_docomplete ()
 {
+  # ignore problem commands
+  grep -q '^-' <<< "$1" && return
+
   complete -o bashdefault -o default -o nospace -F $2 $1 2>/dev/null \
     || complete -o default -o nospace -F $2 $1
 }
@@ -32,21 +35,47 @@ __git-short_shortmap ()
   $( awk "/^$1 / { print \$2 }" <<< "$__git_short_maps" )
 }
 
+__git-short_register_alias ()
+{
+  # ignore invalid aliases (for which we define functions to handle them
+  # instead)
+  grep -q '^-' <<< "$1" && return
+
+  alias $1="__git-short_shortalias $1"
+}
+
 __git-short_shortalias ()
 {
-  cmd=$1
+  shortcmd=$1
   shift
 
   # if we're not within a git dir, fall back to an actual command of this name
   __gitdir >/dev/null || {
-    " $cmd $@"
+    " $shortcmd $@"
     return $?
   }
 
   # execute the command
-  $( grep "^$cmd" <<< "$__git_short_maps" | cut -d' ' -f3- ) "$@"
+  cmd="$( grep "^$shortcmd " <<< "$__git_short_maps" | cut -d' ' -f3- )"
+  if [ -z "$cmd" ]; then
+    return
+  elif [ "$( grep '^|' <<< "$cmd")" ]; then
+    eval "$( sed 's/^|//' <<< "$cmd" ) $@"
+    return $?
+  fi
+
+  $cmd "$@"
 }
 
+# functions that cannot be aliased
+- ()
+{
+  __git-short_shortalias - "$@"
+}
+-- ()
+{
+  __git-short_shortalias -- "$@"
+}
 
 # load shortmaps from cwd (or provided path) and home dir (if available)
 __git_short_maps=$(
@@ -54,6 +83,7 @@ __git_short_maps=$(
     | sed 's/^\([^ ]\+ [^ ]\+\) :/\1 git /'
 )
 
+
 # register each shortmap
 IFS=$'\n'
 for line in $__git_short_maps; do
@@ -63,5 +93,6 @@ for line in $__git_short_maps; do
   [ -z "$1" ] && continue
   __git-short_docomplete "$1" __git-short_shortmap
 
-  alias $1="__git-short_shortalias $1"
+  __git-short_docomplete "$1" __git-short_shortmap
+  __git-short_register_alias "$1"
 done
diff --git a/shortmaps b/shortmaps
index e98afbf..483f547 100644
--- a/shortmaps
+++ b/shortmaps
@@ -12,3 +12,5 @@ s _git_status :status
 S _git_stash :stash
 t void tig
 T _git_tag :tag
+- void :checkout -
+-- void |cd "$( git rev-parse --git-dir 2>/dev/null )/../"