Pez is a small, lightweight, 100% C (for now), embeddable or standalone, public domain, portable, highly nonstandard dialect of Forth. It was originally based on the Atlast system (see doc/CREDITS for more information), but the feature set has been expanded significantly and there are flagrant breaks with Forth compatibility.
The primary goal of the Pez project, much like the goal of the Atlast project, is to bring dead-simple scriptability and dynamism to otherwise static code, with a focus on user-level scripting of applications. There are a number of compile-time options for trimming down and limiting in the case of untrusted input, and also a large number of OS-level facilities both added and planned. Pez is also designed to work well as a stand-alone language for general-purpose coding. And it's designed to be fun.
There are a number of benefits to adding user-level scripting to an application. You get a free doman-specific language to expose to users however you see fit. You get a free configuration file parser in the same language as your application's DSL. You get a dynamic internal scripting language a la LUA. You get a safe, plain-text, cross-platform language for communicating between your applications. It can even be used as a complete, full-featured standalone language. And it's lightweight to boot: running on a 64-bit Linux, I'm looking at about 568k of memory for the REPL for a full system.
Pez has added to the Atlast system a number of features:
- Portability to 64-bit platforms
- A Foreign Function Interface, for dynamically loading libraries to interface with system libraries.
- More complete access to standard system calls, such as fork(), exec(), etc.
- Regular expression support.
- Garbage collection.
- Numerous small improvements, and more large improvements on the way.