Gambit Scheme [1]. Marc started it 34 years ago and still is going strong. Recent versions has support for generating js/php/python/ruby code, but I'm not sure

Gambit Scheme [1]. Marc started it 34 years ago and still is going strong. Recent versions has support for generating js/php/python/ruby code, but I'm not sure what the current state is. One of the most portable and optimizing scheme compilers around. newLISP [2] is still maintained and Lutz is frequent on forum. Kawa Scheme [3], very good optimizing scheme on JVM, started 24 years ago. Per Bothner, author, is frequent on forum, although he'd like someone to continue developing it. PicoLisp [4], started 34 years ago. Alexander Burger is still maintaining it, latest version was 2 months ago. LFE [5], started by Robert Virding (one of Erlang authors), 14 years ago. Still developed. Calibre [6], started 15 years ago by Kovid Goyal. Still in heavy development by Kovid. [1] https://en.wikipedia.org/wiki/Gambit_(Scheme_implementation) https://en.wikipedia.org/wiki/Gambit_(Scheme_implementation) [2] https://en.wikipedia.org/wiki/NewLISP https://en.wikipedia.org/wiki/NewLISP [3] https://en.wikipedia.org/wiki/Kawa_(Scheme_implementation) https://en.wikipedia.org/wiki/Kawa_(Scheme_implementation) [4] https://en.wikipedia.org/wiki/PicoLisp https://en.wikipedia.org/wiki/PicoLisp [5] https://lfe.io/ https://lfe.io/ [6] https://en.wikipedia.org/wiki/Calibre_(software) https://en.wikipedia.org/wiki/Calibre_(software)