Refactor nix files

devkitppc.nix

@@ -1,30 +1,27 @@
-{pkgs ? import <nixpkgs> {}}:
-with pkgs; rec {
-  devkitppc-img = dockerTools.pullImage {
+let
+  pkgs = import <nixpkgs> {};
+  devkitppc-img = pkgs.dockerTools.pullImage {
     imageName = "devkitpro/devkitppc";
     imageDigest = "sha256:77ed88cb417e057fa805e12a8ce1eab8865fe35a761cde7be00315d5c6cba288";
     sha256 = "LLFLDSPJ/tCRBLj0f9q34b5GVHnHudFCgkb7ppMm8VI=";
     finalImageName = "devkitpro/devkitppc";
     finalImageTag = "20200704";
   };
-
-  devkitpro = stdenv.mkDerivation {
+in {
+  devkitpro = pkgs.stdenv.mkDerivation {
     name = "devkitpro";
     src = import ./extract-docker.nix {
+      pkgs = pkgs;
       image = devkitppc-img;
       directory = "/opt/devkitpro";
     };
     nativeBuildInputs = [
-      autoPatchelfHook
+      pkgs.autoPatchelfHook
     ];
     buildInputs = [
-      stdenv.cc.cc
-      openssl
-      zlib
-      libarchive
-      ncurses5
-      expat
-      tlf
+      pkgs.stdenv.cc.cc
+      pkgs.ncurses5
+      pkgs.expat
     ];
     buildPhase = "true";
     installPhase = ''

extract-docker.nix

@@ -1,17 +1,17 @@
 {
+  pkgs,
   image,
   directory,
-  pkgs ? import <nixpkgs> {},
 }:
 pkgs.vmTools.runInLinuxVM (
   pkgs.runCommand "docker-preload-image" {
     memSize = 8 * 1024;
-    buildInputs = with pkgs; [
-      curl
-      kmod
-      docker
-      e2fsprogs
-      utillinux
+    buildInputs = [
+      pkgs.curl
+      pkgs.kmod
+      pkgs.docker
+      pkgs.e2fsprogs
+      pkgs.utillinux
     ];
   }
   ''