Femtolisp – A lightweight, robust, scheme-like Lisp implementation (opens in new tab)

It's hard to imagine there will ever be a more entertaining README. You barely even need to know any of the concepts involved to enjoy it.

I'm hopeful that it gets replaced in the nearish future by a pure Julia parser. Femtolisp is definitely cute, but as other parts of compilation have sped up, Julia's parser has started to show up as a measurable percentage of compile time. Getting a parser written in pure Julia would make it easier to make improvements, and it would be a decent amount faster (see CSTParser.jl which is roughly 10x faster than Julia's built-in parser).

Yes and this makes all the Lisp-like metaprogramming possible!

https://docs.julialang.org/en/v1/manual/metaprogramming/

It's pretty cool, although I haven't used it much myself

The basic set of MS-DOS 3.3 commands, plus TB/TP 5.5, in an HD floppy (1.44), was part of my student kit during highschool that I used to carry around for the labs.

"This is great, but too often I see people omit some of the obscure but critical features that make lisp uniquely wonderful. These include read macros like #. and backreferences, gensyms, and properly escaped symbol names."

Clojure makes a point of having non-extensible reader.

"For example, how does it help to remove backquote? One design changes the syntax of quote. Some systems disallow dotted lists. (I've seen all three of these.) What's the point? Implementers wave the banner of "simplicity", yet wedge in all kinds of weird implicit behaviors and extra evaluation rules."

Not sure about backquote in Clojure, but the next sentence is probably about PicoLisp, which somewhat famously changes `quote` syntax to accept any number of expressions. Disallowing 'dotted lists' is probably also about Clojure, where the lists are not really lists as used in most other Lisps. The "banner of simplicity" can be a reference to "Simple made easy" (IIRC) by Rich Hickey.

"Lately a surprising amount of FUD has been spread about proper tail recursion. [...]"

Not sure here, but out of major lisps Common Lisp doesn't mandate TCO, but at least SBCL does it anyway; while Scheme has TCO in the standard. Clojure doesn't have it, which leads to existence of `recur` (IIRC) and trampolining in user code.

"Bashing" may be too strong a word, even when qualified with "subtle". It might even not be what the author intended at all, it's just what popped up in my head when reading :)