Perl 6

Perl 6 is a major revision to the Perl programming language. It is still in development, as a specification from which several interpreter and compiler implementations are being written. It is introducing elements of many modern and historical languages. Perl 6 is intended to have many implementations. Backward compatibility with earlier versions of Perl is not a goal, though a compatibility mode is part of the specification. The design process for Perl 6 began in 2000.

Development on Pugs, the first high-traction implementation, began in 2005, and today there are multiple Perl 6 implementation projects. Rakudo Perl is based on Parrot and NQP (Not Quite Perl), and releases a new version every month; In July 2010, the project released the first Rakudo Star distribution, a useful and usable collection of a Perl 6 implementation and related materials. Larry Wall maintains a reference grammar known as STD.pm6, written in Perl 6 and bootstrapped with Perl 5.

Niecza, another major Perl 6 implementation, focuses on optimization and efficient implementation research. It targets the Common Language Infrastructure.