diff --git a/nixos/modules/installer/tools/nix-fallback-paths.nix b/nixos/modules/installer/tools/nix-fallback-paths.nix
index 7c5414257b46..6611a6ca0790 100644
--- a/nixos/modules/installer/tools/nix-fallback-paths.nix
+++ b/nixos/modules/installer/tools/nix-fallback-paths.nix
@@ -1,6 +1,6 @@
 {
-  x86_64-linux = "/nix/store/0d60i73mcv8z1m8d2m74yfn84980gfsa-nix-2.0.4";
-  i686-linux = "/nix/store/6ssafj2s5a2g9x28yld7b70vwd6vw6lb-nix-2.0.4";
-  aarch64-linux = "/nix/store/3wwch7bp7n7xsl8apgy2a4b16yzyij1z-nix-2.0.4";
-  x86_64-darwin = "/nix/store/771l8i0mz4c8kry8cz3sz8rr3alalckg-nix-2.0.4";
+  x86_64-linux = "/nix/store/r9i30v8nasafg2851wflg71ln49fw03y-nix-2.1";
+  i686-linux = "/nix/store/dsg3pr7wwrk51f7la9wgby173j18llqh-nix-2.1";
+  aarch64-linux = "/nix/store/m3qgnch4xin21pmd1azas8kkcp9rhkr6-nix-2.1";
+  x86_64-darwin = "/nix/store/n7fvy0k555gwkkdszdkhi3h0aahca8h3-nix-2.1";
 }
diff --git a/pkgs/tools/package-management/nix/default.nix b/pkgs/tools/package-management/nix/default.nix
index bc07dd457f38..a447fbf22827 100644
--- a/pkgs/tools/package-management/nix/default.nix
+++ b/pkgs/tools/package-management/nix/default.nix
@@ -29,7 +29,7 @@ let
 
     buildInputs = [ curl openssl sqlite xz bzip2 ]
       ++ lib.optional (stdenv.isLinux || stdenv.isDarwin) libsodium
-      ++ lib.optionals is20 [ brotli ] # Since 1.12
+      ++ lib.optionals is20 [ brotli boost ]
       ++ lib.optional withLibseccomp libseccomp
       ++ lib.optional ((stdenv.isLinux || stdenv.isDarwin) && is20)
           ((aws-sdk-cpp.override {
@@ -40,8 +40,7 @@ let
               url = https://github.com/edolstra/aws-sdk-cpp/commit/7d58e303159b2fb343af9a1ec4512238efa147c7.patch;
               sha256 = "103phn6kyvs1yc7fibyin3lgxz699qakhw671kl207484im55id1";
             })];
-          }))
-      ++ lib.optional fromGit boost;
+          }));
 
     propagatedBuildInputs = [ boehmgc ];
 
@@ -51,7 +50,7 @@ let
     preConfigure =
       # Copy libboost_context so we don't get all of Boost in our closure.
       # https://github.com/NixOS/nixpkgs/issues/45462
-      lib.optionalString fromGit
+      lib.optionalString is20
       ''
         mkdir -p $out/lib
         cp ${boost}/lib/libboost_context* $out/lib
@@ -148,10 +147,10 @@ in rec {
   }) // { perl-bindings = nix1; };
 
   nixStable = (common rec {
-    name = "nix-2.0.4";
+    name = "nix-2.1";
     src = fetchurl {
       url = "http://nixos.org/releases/nix/${name}/${name}.tar.xz";
-      sha256 = "166540ff7b8bb41449586b67e5fc6ab9e25525f6724b6c6bcbfb0648fbd6496b";
+      sha256 = "0ed68e0c50f13810768fcf510abb2c56d735172c39a325aac7453ccf7ae152fc";
     };
   }) // { perl-bindings = perl-bindings { nix = nixStable; }; };