diff --git a/pkgs/os-specific/linux/minimal-bootstrap/default.nix b/pkgs/os-specific/linux/minimal-bootstrap/default.nix
index 510f0e047ec0..98559814f692 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/default.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/default.nix
@@ -10,7 +10,7 @@ lib.makeScope newScope (self: with self; {
     inherit system;
   };
 
-  inherit (callPackage ./stage0-posix { }) kaem m2libc mescc-tools mescc-tools-extra writeTextFile writeText runCommand;
+  inherit (callPackage ./stage0-posix { }) kaem m2libc mescc-tools mescc-tools-extra writeTextFile writeText runCommand fetchtarball;
 
   mes = callPackage ./mes { };
 
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/mes/default.nix b/pkgs/os-specific/linux/minimal-bootstrap/mes/default.nix
index 6c179c4fbfec..50433c40e7d7 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/mes/default.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/mes/default.nix
@@ -1,5 +1,6 @@
 { runCommand
 , fetchurl
+, fetchtarball
 , writeText
 , m2libc
 , mescc-tools
@@ -14,10 +15,10 @@ let
   };
 
   nyaccVersion = "1.00.2";
-  nyaccModules = builtins.fetchTarball {
-    url = "http://download.savannah.nongnu.org/releases/nyacc/nyacc-${nyaccVersion}.tar.gz";
-    sha256 = "06rg6pn4k8smyydwls1abc9h702cri3z65ac9gvc4rxxklpynslk";
-  };
+  nyaccModules = (fetchtarball {
+    url = "mirror://savannah/nyacc/nyacc-${nyaccVersion}.tar.gz";
+    sha256 = "065ksalfllbdrzl12dz9d9dcxrv97wqxblslngsc6kajvnvlyvpk";
+  }) + "/nyacc-${nyaccVersion}";
 in
 # Adapted from https://github.com/fosslinux/live-bootstrap/blob/1bc4296091c51f53a5598050c8956d16e945b0f5/sysa/mes-0.24.2/mes-0.24.2.kaem
 (runCommand "mes-${version}" {} ''
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/default.nix b/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/default.nix
index ca015991a9d8..a5324633a4f7 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/default.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/default.nix
@@ -40,7 +40,7 @@ lib.makeScope newScope (self: with self; {
 
   mescc-tools-extra = callPackage ./mescc-tools-extra { };
 
-  inherit (callPackage ./utils.nix { }) writeTextFile writeText runCommand;
+  inherit (callPackage ./utils.nix { }) writeTextFile writeText runCommand fetchtarball;
 
   # Now that mescc-tools-extra is available we can install kaem at /bin/kaem
   # to make it findable in environments
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/utils.nix b/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/utils.nix
index ce579c3d2210..b24b8ffdf5c0 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/utils.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/utils.nix
@@ -1,6 +1,7 @@
 { lib
 , system
 , mkKaemDerivation0
+, fetchurl
 , kaem
 , mescc-tools
 , mescc-tools-extra
@@ -48,4 +49,25 @@ rec {
 
       PATH = lib.makeBinPath ((env.nativeBuildInputs or []) ++ [ kaem mescc-tools mescc-tools-extra ]);
     } // (builtins.removeAttrs env [ "nativeBuildInputs" ]));
+
+  # Fetch and unpack a .tar.gz file. Does not strip top-level directory
+  fetchtarball =
+    { url
+      # Unlike fetchzip, this hash is of the tarball and not the decompressed output
+    , sha256
+    , name ? baseNameOf (toString url)
+    , postFetch ? ""
+    }:
+    let
+      tarball = fetchurl { inherit url sha256; };
+    in
+    runCommand name {} ''
+      cd ''${TMP}
+      ungz --file ${tarball} --output tmp.tar
+      mkdir ''${out}
+      cd ''${out}
+      untar --file ''${TMP}/tmp.tar
+
+      ${postFetch}
+    '';
 }
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/tinycc/bootstrappable.nix b/pkgs/os-specific/linux/minimal-bootstrap/tinycc/bootstrappable.nix
index ba57c794fa4c..0884656dc00f 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/tinycc/bootstrappable.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/tinycc/bootstrappable.nix
@@ -3,17 +3,18 @@
 
 { lib
 , runCommand
-, fetchurl
+, fetchtarball
 , mes
 , buildTinyccN
 , unified-libc
 }:
 let
   version = "unstable-2023-04-20";
-  src = builtins.fetchTarball {
-    url = "https://gitlab.com/janneke/tinycc/-/archive/80114c4da6b17fbaabb399cc29f427e368309bc8/tinycc-80114c4da6b17fbaabb399cc29f427e368309bc8.tar.gz";
-    sha256 = "1xhn5qgph32dlxp3fkl4d78f21hvlb2r5dpxvh295x8spkbmbrwp";
-  };
+  rev = "80114c4da6b17fbaabb399cc29f427e368309bc8";
+  src = (fetchtarball {
+    url = "https://gitlab.com/janneke/tinycc/-/archive/${rev}/tinycc-${rev}.tar.gz";
+    sha256 = "1a0cw9a62qc76qqn5sjmp3xrbbvsz2dxrw21lrnx9q0s74mwaxbq";
+  }) + "/tinycc-${rev}";
 
   mes-tcc = runCommand "mes-tcc-${version}" {} ''
     # Create config.h
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/tinycc/default.nix b/pkgs/os-specific/linux/minimal-bootstrap/tinycc/default.nix
index cd1a5397f212..961f259189cc 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/tinycc/default.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/tinycc/default.nix
@@ -1,15 +1,15 @@
 { lib
 , runCommand
-, fetchurl
+, fetchtarball
 , callPackage
 , mes
 }:
 let
   version = "unstable-2023-04-20";
-  src = builtins.fetchTarball {
+  src = (fetchtarball {
     url = "https://repo.or.cz/tinycc.git/snapshot/86f3d8e33105435946383aee52487b5ddf918140.tar.gz";
-    sha256 = "009xvbiskg2ims2xag8w78yksnrqpm33asq5arxaph05hd59yss0";
-  };
+    sha256 = "11idrvbwfgj1d03crv994mpbbbyg63j1k64lw1gjy7mkiifw2xap";
+  }) + "/tinycc-86f3d8e";
 
   unified-libc = runCommand "mes-unified-libc.c" {} ''
     cd ${mes}${mes.mesPrefix}/lib