Hi,

The Medley release of Xerox Interlisp-D has been open sourced under the 
MIT licence. Medley is/was an Interlisp/Common Lisp system that, like 
Smalltalk, ran on the Xerox D* machines and, also like Smalltalk, has a 
very interactive, image-based development style. I'm given to understand 
that it's very much like a Smalltalk environment using Lisp as it's 
language.

Sorry that this is kinda off topic but I thought it would be interesting 
to Squeakers to know that a sort of sibling of the original Smalltalks 
had escaped from the propriety world like Squeak did :)

More info here
https://interlisp.org/
https://github.com/Interlisp