self: super:
let
  msmtp = super.msmtp.overrideAttrs (attrs: rec {
    configureFlags = attrs.configureFlags ++ [ "--with-tls=openssl" ];
    buildInputs = attrs.buildInputs ++ [ super.openssl ];
  });

  lib = super.lib;
  squashfsTools = super.squashfsTools;
  cryptsetup = super.cryptsetup;

  singularity = super.singularity.overrideAttrs (attrs: rec {
      installPhase = ''
        runHook preInstall
        make -C builddir install LOCALSTATEDIR=$out/var
        chmod 755 $out/libexec/singularity/bin/starter-suid

        # Explicitly configure paths in the config file
        sed -i 's|^# mksquashfs path =.*$|mksquashfs path = ${lib.makeBinPath [squashfsTools]}/mksquashfs|' $out/etc/singularity/singularity.conf
        sed -i 's|^# cryptsetup path =.*$|cryptsetup path = ${lib.makeBinPath [cryptsetup]}/cryptsetup|' $out/etc/singularity/singularity.conf
        sed -i 's|^shared loop devices = no|shared loop devices = yes|' $out/etc/singularity/singularity.conf

        runHook postInstall
      '';
  });
in
{
    inherit singularity;
    # inherit msmtp;
}