diff --git a/configs/alias_useful.fish b/configs/alias_useful.fish
index 6205c1d..fc14df0 100755
--- a/configs/alias_useful.fish
+++ b/configs/alias_useful.fish
@@ -287,7 +287,7 @@ end
 
 ################ GREP #########################################################
 
-if test -e /usr/bin/ugrep
+if command -q ugrep
     alias grep='ugrep --color=auto'
     alias egrep='ugrep -E --color=auto'
     alias fgrep='ugrep -F --color=auto'
@@ -296,6 +296,12 @@ else
     alias fgrep='grep -F'
 end
 
+if command -q ugrep
+    alias igrep='ugrep --color=auto --invert-match'
+else if command -q grep
+    alias igrep='grep --color=auto --invert-match'
+end
+
 ################ WGET #########################################################
 
 if test -e /usr/bin/wget