diff --git a/pkgs/tools/package-management/nix/default.nix b/pkgs/tools/package-management/nix/default.nix
index 159fc5b39c1..29a418f3c85 100644
--- a/pkgs/tools/package-management/nix/default.nix
+++ b/pkgs/tools/package-management/nix/default.nix
@@ -119,9 +119,12 @@ common =
         [ "--with-store-dir=${storeDir}"
           "--localstatedir=${stateDir}"
           "--sysconfdir=${confDir}"
-          "--disable-init-state"
           "--enable-gc"
         ]
+        ++ lib.optionals (!is24) [
+          # option was removed in 2.4
+          "--disable-init-state"
+        ]
         ++ lib.optionals stdenv.isLinux [
           "--with-sandbox-shell=${sh}/bin/busybox"
         ]
@@ -208,23 +211,17 @@ in rec {
   nixUnstable = lib.lowPrio (callPackage common rec {
     pname = "nix";
     version = "2.4${suffix}";
-    suffix = "pre20210503_6d2553a";
+    suffix = "pre20210601_5985b8b";
 
     src = fetchFromGitHub {
       owner = "NixOS";
       repo = "nix";
-      rev = "6d2553ae1496288554e871c530836428f405fd67";
-      sha256 = "sha256-YeSeyOKhBAXHlkzo4mwYr8QIjIP9AgdpJ7YdhqOO2CA=";
+      rev = "5985b8b5275605ddd5e92e2f0a7a9f494ac6e35d";
+      sha256 = "sha256-2So7ZsD8QJlOXCYqdoj8naNgBw6O4Vw1MM2ORsaqlXc=";
     };
 
     inherit storeDir stateDir confDir boehmgc;
 
-    patches = [
-      (fetchpatch {
-        url = "https://github.com/NixOS/nix/commit/8c7e043de2f673bc355d83f1e873baa93f30be62.patch";
-        sha256 = "sha256-aTcUnZXheewnyCT7yQKnTqQDKS2uDoN9plMQgxJH8Ag=";
-      })
-    ];
   });
 
 }