anchor.diff:      gnutls
       gsettings-desktop-schemas
       libproxy
  -    p11_kit
  +    p11-kit
     ];
   
     configureFlags = [
  
positive.code:     "--with-gnome-proxy"
      "--${boolWt (gnutls != null)}-gnutls"
      "--with-ca-certificates=/etc/ssl/certs/ca-certificates.crt"
      "--${boolWt (p11_kit != null)}-pkcs11"
    ];
  
    preBuild = ''
  
negative.code: , gnutls
  , gsettings-desktop-schemas
  , libproxy
  , p11-kit
  
  , channel
  }:
  