Retro is a modern, pragmatic Forth drawing influences from many
sources. It's clean, elegant, tiny, and easy to grasp and adapt
to various uses.
- Open Source (ISC License)
- Portable (runs on a MISC-style virtual machine)
- Small source & binaries
- Builds into a single, self contained binary for easy deployment
- Sources in literate format, using a Markdown variant
## Quick Start
For most systems (FreeBSD, NetBSD, OpenBSD, macOS, Linux):
You will need a standard C compiler and `make`.
Binaries will be placed in the `bin` directory.
The primary executable is `retro`. This is used for running the
examples and the Atua (gopher) & Casket (http) servers that
The `retro` executable embeds the image into the binary, making
it trivial to copy and deploy.
This interface layer also extends the language with many new
words and vocabularies, adds scripting, file i/o, floating point,
The `retro` executable can handle a variety of command line
arguments which are covered in the manpage, but the most common
Starts the *listener*, a basic REPL for interactive use.
This will run the code in the specified file, then exit. This
is also used to run programs as shell-type scripts using a
header line like `#!/usr/bin/env retro`.
retro -i -f filename
This will run the code in the specified file, then start the
## Literate Sources
Source files for use with `retro` are written with code in
Anything outside the fenced blocks will be ignored.
The primary documentation is in RETRO-Book.md (and the formatted
epub.) Additional notes can be found in the `doc` directory.
## Alternative Implementations
In addition to the C and Python implementations, this source
and Pascal. These are not as well tested or as feature complete
as the main implementations, but are provided for your use if
the standard implementations will not suffice.
I have a Patreon at https://www.patreon.com/_crc for those that
want to financially support development. All funds raised via
Pateron are put into development related expenses (server expenses,
app store fees, hardware).
Thanks go out to my current and past patrons:
- Kiyoshi YONEDA
- Rick Carlino
- Scott McCallum
- Bartels Jon Randy