Bravo bliako :-) However, the behavior of that module's build process is still bizarro. I went into ./_build and grepped for '0.011' and found file build_params to contain:
    'dist_abstract' => 'Querying your filehandle\'s capabilities',
    'dist_version' => '0.011',
    'build_bat' => 0,
    'dynamic_config' => 1,
    'c_source' => undef,
    'extra_compiler_flags' => [],
    'verbose' => undef,
    'build_class' => 'Module::Build',
    'quiet' => undef,
    'install_sets' => {},
    'use_rcfile' => 1,
    '_added_to_INC' => [
      '/Users/carly/perl5/lib/perl5/5.18.2/darwin-thread-multi-2level'
+,
      '/Users/carly/perl5/lib/perl5/5.18.2',
      '/Users/carly/perl5/lib/perl5/darwin-thread-multi-2level',
      '/Users/carly/perl5/lib/perl5',
      '/Users/carly/src/perl5/lib'
    ],

[download]
among other expressions. This is obviously not a hand-generated file. So, I double quoted that version number => "0.011" and then did 'perl ./Build.PL' and then Build and 'Build test'. Like magic, all was well, all tests were successful but... get this, the module Module::Build as in: 
# This should have just enough arguments to be able to bootstrap the r
+est.
my $build = Module::Build->resume (
  properties => {
    config_dir => '_build',
    orig_dir => $orig_dir,
  },
);

$build->dispatch;

[download]
reset that double-quoted string to '0.011'. Man, talk about perverse. I poked Leon Timmerman's, the author/maintainer of PerlIO::Layers with this issue but have yet to hear back. How do we alert all of the Perl-heads who might be inadvertently creating this problem?

In reply to Re^2: PerlIO::Layers 0.011 fails to build in macOS 10.13.3 by perlboy_emeritus
in thread PerlIO::Layers 0.011 fails to build in macOS 10.13.3 by perlboy_emeritus

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