anchor.diff:  # based on https://github.com/nim-lang/Nim/blob/v0.18.0/.travis.yml
   
  -{ stdenv, lib, fetchurl, makeWrapper, nodejs-slim-11_x, openssl, pcre, readline,
  +{ stdenv, lib, fetchurl, makeWrapper, nodejs-slim, openssl, pcre, readline,
     boehmgc, sfml, tzdata, coreutils, sqlite }:
   
   stdenv.mkDerivation rec {
     pname = "nim";
  -  version = "0.20.2";
  +  version = "1.0.0";
   
     src = fetchurl {
       url = "https://nim-lang.org/download/${pname}-${version}.tar.xz";
  -    sha256 = "0pibil10x0c181kw705phlwk8bn8dy5ghqd9h9fm6i9afrz5ryp1";
  +    sha256 = "1pg0lxahis8zfk6rdzdj281bahl8wglpjgngkc4vg1pc9p61fj03";
     };
   
     doCheck = !stdenv.isDarwin;
  
positive.code:       ${disableCompile} ./lib/nimhcr.nim
        ${disableTest} ./tests/dll/nimhcr_unit.nim
        ${disableTest} ./tests/dll/nimhcr_integration.nim
      '';
  
    checkPhase = ''
      runHook preCheck
  
      ./koch tests --nim:bin/nim all
  
      runHook postCheck
  
negative.code:       substituteInPlace ./tests/osproc/tworkingdir.nim --replace "/usr/bin" "${coreutils}/bin"
        substituteInPlace ./tests/stdlib/ttimes.nim --replace "/usr/share/zoneinfo" "${tzdata}/share/zoneinfo"
  
        # runs out of memory on a machine with 8GB RAM
        ${disableTest} ./tests/system/t7894.nim
  
  