diff --git a/rc/functions.sh b/rc/functions.sh
index 4569f1e..40bb19c 100644
--- a/rc/functions.sh
+++ b/rc/functions.sh
@@ -1,5 +1,6 @@
+# $LWS/rc/functions.sh
 
-function jql() { 
+function jql() {
   jq -C . "$@" | less -r
 }
 
@@ -13,3 +14,21 @@ function ffile() {
 function utime() {
   date '+%s.%N'
 }
+
+function in_path() {
+  [[ "$PATH" =~ (^|:)"${1}"(:|$) ]]
+}
+
+function append_path() {
+  if ! in_path "$1"; then
+    PATH="$PATH:$1"
+  fi
+}
+
+function prepend_path() {
+  if ! in_path "$1"; then
+    PATH="$1:$PATH"
+  fi
+}
+
+