Once? This is the only time there has been a release of a versioned specification for the <i></i><i>language</i><i></i> compilers can target. That&#x27;s what has been in development for 15 years! The specification of the actual language. It&#x27;s like the difference between JavaScript existing as a language for a while and then one day ECMAScript 1 was defined. Apart from Perl 6 was always about the evolution of the spec with various implementations showing the way.<p>The first major implementation of Perl 6 back in the early&#x2F;mid 00s was Pugs written in Haskell where Perl 6 picked up a tonne of functional heritage both in the compiler at the time and the language spec. The more recent Rakudo compiler has a lead architect who often works in C# where the compiler and the language spec picked up and redefined a reactive programming concurrency model with lots of nice new syntax like the react&#x2F;whenever block.<p>Rakudo Perl 6 and Pugs and the host of other early implementations have been around a while and released often when they were worked on, monthly in the case of Rakudo with the first publicised release in 2010. Rakudo is also releasing a version of the compiler compliant with the newly frozen and released specification.