{ useLua ? true
, usePcre ? true
, withPrometheusExporter ? true
, sslLibrary ? "quictls"
, stdenv
, lib
, fetchurl
, nixosTests
, zlib
, libxcrypt
, wolfssl
, libressl
, quictls
, openssl
, lua5_4
, pcre2
}:

assert lib.assertOneOf "sslLibrary" sslLibrary [ "quictls" "openssl" "libressl" "wolfssl" ];
let
  sslPkgs = {
    inherit quictls openssl libressl;
    wolfssl = wolfssl.override {
      variant = "haproxy";
      extraConfigureFlags = [ "--enable-quic" ];
    };
  };
  sslPkg = sslPkgs.${sslLibrary};
in stdenv.mkDerivation (finalAttrs: {
  pname = "haproxy";
  version = "3.0.3";

  src = fetchurl {
    url = "https://www.haproxy.org/download/${lib.versions.majorMinor finalAttrs.version}/src/haproxy-${finalAttrs.version}.tar.gz";
    hash = "sha256-Oac8GHoLANJgLLP/ylLRtZ2Q8JAyc0/owD6y4pp9Gd8=";
  };

  buildInputs = [ sslPkg zlib libxcrypt ]
    ++ lib.optional useLua lua5_4
    ++ lib.optional usePcre pcre2;

  # TODO: make it work on bsd as well
  makeFlags = [
    "PREFIX=${placeholder "out"}"
    ("TARGET=" + (if stdenv.isSunOS then "solaris"
    else if stdenv.isLinux then "linux-glibc"
    else if stdenv.isDarwin then "osx"
    else "generic"))
  ];

  buildFlags = [
    "USE_ZLIB=yes"
    "USE_OPENSSL=yes"
    "SSL_INC=${lib.getDev sslPkg}/include"
    "SSL_LIB=${lib.getDev sslPkg}/lib"
    "USE_QUIC=yes"
  ] ++ lib.optionals (sslLibrary == "openssl") [
    "USE_QUIC_OPENSSL_COMPAT=yes"
  ] ++ lib.optionals (sslLibrary == "wolfssl") [
    "USE_OPENSSL_WOLFSSL=yes"
  ] ++ lib.optionals usePcre [
    "USE_PCRE2=yes"
    "USE_PCRE2_JIT=yes"
  ] ++ lib.optionals useLua [
    "USE_LUA=yes"
    "LUA_LIB_NAME=lua"
    "LUA_LIB=${lua5_4}/lib"
    "LUA_INC=${lua5_4}/include"
  ] ++ lib.optionals stdenv.isLinux [
    "USE_SYSTEMD=yes"
    "USE_GETADDRINFO=1"
  ] ++ lib.optionals withPrometheusExporter [
    "USE_PROMEX=yes"
  ] ++ [ "CC=${stdenv.cc.targetPrefix}cc" ];

  enableParallelBuilding = true;

  passthru.tests.haproxy = nixosTests.haproxy;

  meta = {
    changelog = "https://www.haproxy.org/download/${lib.versions.majorMinor finalAttrs.version}/src/CHANGELOG";
    description = "Reliable, high performance TCP/HTTP load balancer";
    homepage = "https://haproxy.org";
    license = with lib.licenses; [ gpl2Plus lgpl21Only ];
    longDescription = ''
      HAProxy is a free, very fast and reliable solution offering high
      availability, load balancing, and proxying for TCP and HTTP-based
      applications. It is particularly suited for web sites crawling under very
      high loads while needing persistence or Layer7 processing. Supporting
      tens of thousands of connections is clearly realistic with todays
      hardware.
    '';
    maintainers = with lib.maintainers; [ vifino ];
    platforms = with lib.platforms; linux ++ darwin;
    mainProgram = "haproxy";
  };
})
