diff --git a/pkgs/by-name/is/isc-cron/0000-nixpkgs-specific.diff b/pkgs/by-name/is/isc-cron/0000-nixpkgs-specific.diff
index 0bf0a9bd6177..9bf9f89ddee2 100644
--- a/pkgs/by-name/is/isc-cron/0000-nixpkgs-specific.diff
+++ b/pkgs/by-name/is/isc-cron/0000-nixpkgs-specific.diff
@@ -35,10 +35,10 @@ diff -Naur cron-old/pathnames.h cron-new/pathnames.h
 +#define _PATH_SENDMAIL "@sendmailPath@"
 +
 +#undef _PATH_VI
-+#define _PATH_VI "@VIPATH@"
++#define _PATH_VI "@viPath@"
 +
 +#undef _PATH_DEFPATH
-+#define _PATH_DEFPATH "@DEFPATH@"
++#define _PATH_DEFPATH "@defPath@"
 +
 +/* Nixpkgs-specific patch end */
 +
diff --git a/pkgs/by-name/is/isc-cron/package.nix b/pkgs/by-name/is/isc-cron/package.nix
index b52086fca473..61633c6c9c88 100644
--- a/pkgs/by-name/is/isc-cron/package.nix
+++ b/pkgs/by-name/is/isc-cron/package.nix
@@ -20,8 +20,8 @@ stdenv.mkDerivation (finalAttrs: {
     (substituteAll {
       src = ./0000-nixpkgs-specific.diff;
       inherit sendmailPath;
-      VIPATH = lib.getExe' vim "vim";
-      DEFPATH = lib.concatStringsSep ":" [
+      viPath = lib.getExe' vim "vim";
+      defPath = lib.concatStringsSep ":" [
         "/run/wrappers/bin"
         "/nix/var/nix/profiles/default/bin"
         "/run/current-system/sw/bin"