Perl 11 is not (yet) an actual version of Perl; rather, Perl 11 is currently a philosophy with 3 primary tenets:
Perl 11 promotes ideas which will make Perl 5 pluggable at the following levels:
This will open up the doors to many kinds of language / technology experimentation, without endangering the existing Perl 5 / CPAN code bases that we depend on every day.
Pluggable VMs would be parrot, p2, JVM or .NET running Perl 5 and Perl 6 Raku code. 5 + 6 == 11!
The following projects are important in reaching the vision of Perl 11:
A Restricted Perl by Will Braswell which translates a medium-magic subset of Perl 5 into C/C++ using Inline::C and Inline::CPP
cperl is an improved variant of Perl 5, running all of Perl 5 and CPAN code. With many Perl 6 Raku features, just faster.
Faster than Perl 5 and Perl 6 Raku. It is stable and usable, but still in development with many more features being added soon.
WebPerl is a port of the entire Perl 5 interpreter running inside a modern web browser.
WebPerl is compiled using clang/LLVM/Emscripten targeting WebAssembly, and can replace JavaScript as a client-side execution platform, complete with XS support!
p2 by Reini Urban was the attempt to be a fast, small perl11 (5+6 and more) using the potion vm.
potion is the VM behind p2, a small fast language, written by _why's, based on lua, io and others.
Perlito by Flavio Glock is a source level compiler for translating Perl 5 and Perl 6 Raku to Javascript and other backends.
perl6/std with the viv metacompiler contains the canonical Perl 6 Raku grammar and now also a Perl 5 grammar. Written in Perl 6 Raku, interpreted and compiled in Perl 5 (via viv).
gperl by Masaaki Goshima compiles to heavily optimized LLVM and is ~3x faster than p2. Currrently it is being decoupled to different Perl 5 compiler modules.
Seis is a project by Tokuhiro Matsuno to try some Perl 6 Raku extensions in Perl 5.
pviv is a Perl 6 Raku grammar written in greg, which compiles to an AST and will be used as the Perl 6 Raku grammar for p2.
SPVM by Yuki Kimoto, a fast & small virtual machine with Perl'ish syntax.