diff --git a/pkgs/tools/system/plan9port/builder.sh b/pkgs/tools/system/plan9port/builder.sh
index 77f6632ff533..f5c447ea0a53 100644
--- a/pkgs/tools/system/plan9port/builder.sh
+++ b/pkgs/tools/system/plan9port/builder.sh
@@ -22,7 +22,7 @@ plan9portLinkFlags()
 configurePhase()
 {
     (
-        echo CC9=\"$(which $CC)\"
+        echo CC9=\"$(command -v $CC)\"
         echo CFLAGS=\"$NIX_CFLAGS_COMPILE\"
         echo LDFLAGS=\"$(plan9portLinkFlags)\"
         echo X11=\"${libXt_dev}/include\"