Is a light-weight implementation of Standard ML (SML), a strict functional language widely used in teaching and research. Web site https://mosml.org/ The Moscow ML implementation can be found at https://github.com/kfl/mosml.
Is a fast and portable implementation of the ANS Forth/Forth 200x language. It works nicely with the Emacs editor, offers some nice features such as input completion and history, backtraces, a decompiler and a powerful locals facility, and it has a comprehensive manual. Gforth combines traditional implementation techniques with newer techniques for portability and performance: its inner interpreter is direct threaded with several optimizations, but you can also use a traditional-style indirect threaded interpreter. Gforth is distributed under the GNU General Public license (see COPYING). The Gforth implementation can be found at https://github.com/forthy42/gforth
Is c.