diff --git a/asdf.fish b/asdf.fish
index 854bcf11..e9d2a3b6 100644
--- a/asdf.fish
+++ b/asdf.fish
@@ -1,4 +1,6 @@
-set -x ASDF_DIR (dirname (status -f))
+if not set -q ASDF_DIR
+  set -x ASDF_DIR (dirname (status -f))
+end
 
 set -l asdf_user_shims (
   if test -n "$ASDF_DATA_DIR"