anchor.diff:      "
   
       # Use updated rust version
  -    echo "export PATH=${rustChannel.rust}/bin:${rustChannel.cargo}/bin:\$PATH" >> $geckoenv
  +    echo "export PATH=${rust-cbindgen}/bin:${rustChannel.rust}/bin:${rustChannel.cargo}/bin:\$PATH" >> $geckoenv
     '';
     installPhase = ''
       geckoenv=$out/bin/gecko-env
  
positive.code:   inherit (releng_pkgs.pkgs) rustChannelOf bash autoconf213 clang_4 llvm_4 llvmPackages_4 gcc-unwrapped glibc fetchFromGitHub unzip zip openjdk python2Packages sqlite zlib;
    inherit (releng_pkgs.pkgs.devEnv) gecko;
  
    # Rust 1.29.1
    rustChannel' = rustChannelOf { date = "2018-09-25"; channel = "stable"; };
    rustChannel = { inherit (rustChannel') cargo; rust = rustChannel'.rust.override { targets=["armv7-linux-androideabi"]; }; };
  
    # Add missing gcc libraries needed by clang (see https://github.com/mozilla/release-services/issues/1256)
  
negative.code: 
    # Mach needs 0.6.7 at least
    # From https://github.com/NixOS/nixpkgs/blob/cdf90258e6bf911db2b56280301014a88c91be65/pkgs/development/tools/rust/cbindgen/default.nix
    rustPlatform = mkRustPlatform {
      rust = {
        cargo = rustChannel.cargo;
        rustc = rustChannel.rust;
      };
    };
    rust-cbindgen =  rustPlatform.buildRustPackage rec {
      name = "rust-cbindgen-${version}";
      version = "0.6.7";
  