anchor.diff:    + lib.concatMapStrings
       (pkg: lib.optionalString (pkg ? dev) " --replace '-L${pkg.dev}/lib' '-L${pkg.out}/lib' --replace '-R${pkg.dev}/lib' '-R${pkg.out}/lib'")
       (builtins.filter (p: p != null) buildInputs);
  +
  +  passthru.tests = nixosTests.unbound;
   
     meta = with lib; {
       description = "Validating, recursive, and caching DNS resolver";
  
positive.code:       configureFlags="$configureFlags --with-nettle=${nettle.dev} --with-libunbound-only"
        configurePhase
        buildPhase
        installPhase
      ''
    # get rid of runtime dependencies on $dev outputs
  
negative.code:     sed -E '/CONFCMDLINE/ s;${storeDir}/[a-z0-9]{32}-;${storeDir}/eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-;g' -i config.h
    '';
  
    checkInputs = [ bison ];
  
    doCheck = true;
  
    installFlags = [ "configfile=\${out}/etc/unbound/unbound.conf" ];
  
    postInstall = ''
  