There's a great book from the late 70s / early 80s called "Threaded Interpretive Languages" by R. G. Loeliger. It's apparently up on the Internet Archive for free and worth a look if you're interested in threaded interpreters. I nano-blogged it at: <a href="https://www.bi6.us/CO/N/20250427.HTML#/043002" rel="nofollow">https://www.bi6.us/CO/N/20250427.HTML#/043002</a>