diff --git a/flake.nix b/flake.nix
index aab009d..bc3fa0a 100644
--- a/flake.nix
+++ b/flake.nix
@@ -8,7 +8,6 @@
     let
       pkgs = import nixpkgs { system = "x86_64-linux"; overlays = [ (import mozilla-overlay) ]; };
       
-      # ==== rustPlatform
       rustManifest = pkgs.fetchurl {
         url = "https://static.rust-lang.org/dist/2021-01-29/channel-rust-nightly.toml";
         sha256 = "sha256-EZKgw89AH4vxaJpUHmIMzMW/80wAFQlfcxRoBD9nz0c=";
@@ -26,120 +25,120 @@
         rustc = rust;
         cargo = rust;
       });
-      # ==== rustPlatform / gnutoolchain
-        gnu-platform = "arm-none-eabi";
 
-        binutils-pkg = { zlib, extraConfigureFlags ? [] }: pkgs.stdenv.mkDerivation rec {
-          basename = "binutils";
-          version = "2.30";
-          name = "${basename}-${gnu-platform}-${version}";
-          src = pkgs.fetchurl {
-            url = "https://ftp.gnu.org/gnu/binutils/binutils-${version}.tar.bz2";
-            sha256 = "028cklfqaab24glva1ks2aqa1zxa6w6xmc8q34zs1sb7h22dxspg";
-          };
-          configureFlags = [
-            "--enable-deterministic-archives"
-            "--target=${gnu-platform}"
-            "--with-cpu=cortex-a9"
-            "--with-fpu=vfpv3"
-            "--with-float=hard"
-            "--with-mode=thumb"
-          ] ++ extraConfigureFlags;
-          outputs = [ "out" "info" "man" ];
-          depsBuildBuild = [ pkgs.buildPackages.stdenv.cc ];
-          buildInputs = [ zlib ];
-          enableParallelBuilding = true;
-          meta = {
-            description = "Tools for manipulating binaries (linker, assembler, etc.)";
-            longDescription = ''
-              The GNU Binutils are a collection of binary tools.  The main
-              ones are `ld' (the GNU linker) and `as' (the GNU assembler).
-              They also include the BFD (Binary File Descriptor) library,
-              `gprof', `nm', `strip', etc.
-            '';
-            homepage = http://www.gnu.org/software/binutils/;
-            license = pkgs.lib.licenses.gpl3Plus;
-            /* Give binutils a lower priority than gcc-wrapper to prevent a
-              collision due to the ld/as wrappers/symlinks in the latter. */
-            priority = "10";
-          };
+      gnu-platform = "arm-none-eabi";
+
+      binutils-pkg = { zlib, extraConfigureFlags ? [] }: pkgs.stdenv.mkDerivation rec {
+        basename = "binutils";
+        version = "2.30";
+        name = "${basename}-${gnu-platform}-${version}";
+        src = pkgs.fetchurl {
+          url = "https://ftp.gnu.org/gnu/binutils/binutils-${version}.tar.bz2";
+          sha256 = "028cklfqaab24glva1ks2aqa1zxa6w6xmc8q34zs1sb7h22dxspg";
         };
-
-        gcc-pkg = { gmp, mpfr, libmpc, platform-binutils, extraConfigureFlags ? [] }: pkgs.stdenv.mkDerivation rec {
-          basename = "gcc";
-          version = "9.1.0";
-          name = "${basename}-${gnu-platform}-${version}";
-          src = pkgs.fetchurl {
-            url = "https://ftp.gnu.org/gnu/gcc/gcc-${version}/gcc-${version}.tar.xz";
-            sha256 = "1817nc2bqdc251k0lpc51cimna7v68xjrnvqzvc50q3ax4s6i9kr";
-          };
-          preConfigure = ''
-            mkdir build
-            cd build
+        configureFlags = [
+          "--enable-deterministic-archives"
+          "--target=${gnu-platform}"
+          "--with-cpu=cortex-a9"
+          "--with-fpu=vfpv3"
+          "--with-float=hard"
+          "--with-mode=thumb"
+        ] ++ extraConfigureFlags;
+        outputs = [ "out" "info" "man" ];
+        depsBuildBuild = [ pkgs.buildPackages.stdenv.cc ];
+        buildInputs = [ zlib ];
+        enableParallelBuilding = true;
+        meta = {
+          description = "Tools for manipulating binaries (linker, assembler, etc.)";
+          longDescription = ''
+            The GNU Binutils are a collection of binary tools.  The main
+            ones are `ld' (the GNU linker) and `as' (the GNU assembler).
+            They also include the BFD (Binary File Descriptor) library,
+            `gprof', `nm', `strip', etc.
           '';
-          configureScript = "../configure";
-          configureFlags = [ 
-            "--target=${gnu-platform}"
-            "--with-arch=armv7-a"
-            "--with-tune=cortex-a9"
-            "--with-fpu=vfpv3"
-            "--with-float=hard"
-            "--disable-libssp"
-            "--enable-languages=c"
-            "--with-as=${platform-binutils}/bin/${gnu-platform}-as"
-            "--with-ld=${platform-binutils}/bin/${gnu-platform}-ld" ] ++ extraConfigureFlags;
-          outputs = [ "out" "info" "man" ];
-          hardeningDisable = [ "format" "pie" ];
-          propagatedBuildInputs = [ gmp mpfr libmpc platform-binutils ];
-          enableParallelBuilding = true;
-          dontFixup = true;
+          homepage = http://www.gnu.org/software/binutils/;
+          license = pkgs.lib.licenses.gpl3Plus;
+          /* Give binutils a lower priority than gcc-wrapper to prevent a
+            collision due to the ld/as wrappers/symlinks in the latter. */
+          priority = "10";
         };
+      };
 
-        newlib-pkg = { platform-binutils, platform-gcc }: pkgs.stdenv.mkDerivation rec {
-          pname = "newlib";
-          version = "3.1.0";
-          src = pkgs.fetchurl {
-            url = "ftp://sourceware.org/pub/newlib/newlib-${version}.tar.gz";
-            sha256 = "0ahh3n079zjp7d9wynggwrnrs27440aac04340chf1p9476a2kzv";
-          };
-          nativeBuildInputs = [ platform-binutils platform-gcc ];
-          configureFlags = [
-            "--target=${gnu-platform}"
-
-            "--with-cpu=cortex-a9"
-            "--with-fpu=vfpv3"
-            "--with-float=hard"
-            "--with-mode=thumb"
-            "--enable-interwork"
-            "--disable-multilib"
-
-            "--disable-newlib-supplied-syscalls"
-            "--with-gnu-ld"
-            "--with-gnu-as"
-            "--disable-newlib-io-float"
-            "--disable-werror"
-          ];
-          dontFixup = true;
+      gcc-pkg = { gmp, mpfr, libmpc, platform-binutils, extraConfigureFlags ? [] }: pkgs.stdenv.mkDerivation rec {
+        basename = "gcc";
+        version = "9.1.0";
+        name = "${basename}-${gnu-platform}-${version}";
+        src = pkgs.fetchurl {
+          url = "https://ftp.gnu.org/gnu/gcc/gcc-${version}/gcc-${version}.tar.xz";
+          sha256 = "1817nc2bqdc251k0lpc51cimna7v68xjrnvqzvc50q3ax4s6i9kr";
         };
-        gnutoolchain = rec {
-          binutils-bootstrap = pkgs.callPackage binutils-pkg { };
-          gcc-bootstrap = pkgs.callPackage gcc-pkg {
-            platform-binutils = binutils-bootstrap;
-            extraConfigureFlags = [ "--disable-libgcc" ];
-          };
-          newlib = pkgs.callPackage newlib-pkg {
-            platform-binutils = binutils-bootstrap;
-            platform-gcc = gcc-bootstrap;
-          };
-          binutils = pkgs.callPackage binutils-pkg {
-            extraConfigureFlags = [ "--with-lib-path=${newlib}/arm-none-eabi/lib" ];
-          };
-          gcc = pkgs.callPackage gcc-pkg {
-            platform-binutils = binutils;
-            extraConfigureFlags = [ "--enable-newlib" "--with-headers=${newlib}/arm-none-eabi/include" ];
-          };
+        preConfigure = ''
+          mkdir build
+          cd build
+        '';
+        configureScript = "../configure";
+        configureFlags = [ 
+          "--target=${gnu-platform}"
+          "--with-arch=armv7-a"
+          "--with-tune=cortex-a9"
+          "--with-fpu=vfpv3"
+          "--with-float=hard"
+          "--disable-libssp"
+          "--enable-languages=c"
+          "--with-as=${platform-binutils}/bin/${gnu-platform}-as"
+          "--with-ld=${platform-binutils}/bin/${gnu-platform}-ld" ] ++ extraConfigureFlags;
+        outputs = [ "out" "info" "man" ];
+        hardeningDisable = [ "format" "pie" ];
+        propagatedBuildInputs = [ gmp mpfr libmpc platform-binutils ];
+        enableParallelBuilding = true;
+        dontFixup = true;
+      };
+
+      newlib-pkg = { platform-binutils, platform-gcc }: pkgs.stdenv.mkDerivation rec {
+        pname = "newlib";
+        version = "3.1.0";
+        src = pkgs.fetchurl {
+          url = "ftp://sourceware.org/pub/newlib/newlib-${version}.tar.gz";
+          sha256 = "0ahh3n079zjp7d9wynggwrnrs27440aac04340chf1p9476a2kzv";
         };
-      # ==== gnutoolchain/cargo-xbuild
+        nativeBuildInputs = [ platform-binutils platform-gcc ];
+        configureFlags = [
+          "--target=${gnu-platform}"
+
+          "--with-cpu=cortex-a9"
+          "--with-fpu=vfpv3"
+          "--with-float=hard"
+          "--with-mode=thumb"
+          "--enable-interwork"
+          "--disable-multilib"
+
+          "--disable-newlib-supplied-syscalls"
+          "--with-gnu-ld"
+          "--with-gnu-as"
+          "--disable-newlib-io-float"
+          "--disable-werror"
+        ];
+        dontFixup = true;
+      };
+      gnutoolchain = rec {
+        binutils-bootstrap = pkgs.callPackage binutils-pkg { };
+        gcc-bootstrap = pkgs.callPackage gcc-pkg {
+          platform-binutils = binutils-bootstrap;
+          extraConfigureFlags = [ "--disable-libgcc" ];
+        };
+        newlib = pkgs.callPackage newlib-pkg {
+          platform-binutils = binutils-bootstrap;
+          platform-gcc = gcc-bootstrap;
+        };
+        binutils = pkgs.callPackage binutils-pkg {
+          extraConfigureFlags = [ "--with-lib-path=${newlib}/arm-none-eabi/lib" ];
+        };
+        gcc = pkgs.callPackage gcc-pkg {
+          platform-binutils = binutils;
+          extraConfigureFlags = [ "--enable-newlib" "--with-headers=${newlib}/arm-none-eabi/include" ];
+        };
+      };
+
       cargo-xbuild = rustPlatform.buildRustPackage rec {
         pname = "cargo-xbuild";
         version = "0.6.5";
@@ -159,7 +158,7 @@
           maintainers = with maintainers; [ johntitor xrelkd ];
         };
       };
-      # ==== cargo-xbuild/mkbootimage
+
       mkbootimage = pkgs.stdenv.mkDerivation {
         pname = "mkbootimage";
         version = "2.2";
@@ -182,7 +181,7 @@
           cp mkbootimage $out/bin
         '';
       };
-      # ==== mkbootimage/fsbl
+
       fsbl = { board ? "zc706" }: pkgs.stdenv.mkDerivation {
         name = "${board}-fsbl";
         src = pkgs.fetchFromGitHub {
@@ -213,7 +212,7 @@
         doCheck = false;
         dontFixup = true;
       };
-    # ==== fsbl/default
+
       cargoSha256Experiments = "1bvffgr4588bbkjwnhim8rvkjvbnajaiv7hc98b19sr8kb7rcj63";
       cargoSha256SZL = "13022ssk6s2fgxmmh5msbx01fzcmk2cj95fjpxcsmfy14k9wd77l";