include correct rust install in nix-shell

rust-toolchain.toml

@@ -1,5 +1,4 @@
 [toolchain]
-channel = "nightly-2023-11-21"
-#components = [ "rustfmt", "rustc-dev" ]
+channel = "nightly"
+date = "2023-11-21"
 targets = [ "x86_64-unknown-linux-gnu" ]
-#profile = "minimal"

shell.nix

@@ -1,8 +1,10 @@
-{ pkgs ? import <nixpkgs> { } }:
-
-with pkgs;
-
-mkShell rec {
+let
+  moz_overlay = import (builtins.fetchTarball https://github.com/mozilla/nixpkgs-mozilla/archive/master.tar.gz);
+  nixpkgs = import <nixpkgs> { overlays = [ moz_overlay ]; };
+in
+  with nixpkgs;
+  stdenv.mkDerivation rec {
+    name = "lyra_engine_dev";
     nativeBuildInputs = [
       pkg-config
       openssl
@@ -13,7 +15,7 @@ mkShell rec {
       mold
       udev
       lua5_4_compat
-    rustup
+      (nixpkgs.rustChannelOf { rustToolchain = ./rust-toolchain.toml; }).rust
     ];
     buildInputs = [
       udev alsa-lib libGL gcc