Mildew is a compiler that uses STD.pm as its parser and SMOP as its runtime. It's mainly developed by Pawel Murias and Daniel Ruoso.
The development of mildew is not feature-oriented, so we support a very small subset of the language features, but that is not really bad news. Mildew development is concept-oriented, so that means we fully support some Perl 6 concepts that are not yet supported by other implementations, like the "return" routine.
Mildew has its own test suite, which is located at http://svn.pugscode.org/pugs/v6/mildew/t/
http://svn.pugscode.org/pugs/v6/mildew/example/cgi.pl
http://svn.pugscode.org/pugs/v6/mildew/t/return_function.t
http://svn.pugscode.org/pugs/v6/mildew/t/throw_inside_catch.t
http://svn.pugscode.org/pugs/v6/mildew/t/control_exception.t
http://svn.pugscode.org/pugs/v6/mildew/t/fail.t
http://svn.pugscode.org/pugs/v6/mildew/t/multi.t
http://svn.pugscode.org/pugs/v6/mildew/t/role.t
http://svn.pugscode.org/pugs/v6/mildew/t/capture_expansion.t
http://svn.pugscode.org/pugs/v6/mildew/t/binding.t
http://svn.pugscode.org/pugs/v6/mildew/t/classhow_add_method.t
http://svn.pugscode.org/pugs/v6/mildew/t/classhow_add_method_real.t
Most of the spec is not yet implemented, take a look at the test suite to see what already works.