fructure VS racket-binfmt

Even the racket teachpack libraries designed for education are very capable; I was able to make this structured editor with only using teachpack content without external deps: https://github.com/disconcision/fructure

Right, it's fine, and is a pretty basic macro. Doubly linked lists are pretty basic data structures too, even the Rust versions once you figure it out. I like your sibling comment making it look like the CL version. I still want to know in more detail though why you think that doing things this way instead of the CL way is less likely to be "fragile and break down" for the complicated stuff, it would help to have a specific complicated example to showcase. Perhaps the linked https://github.com/disconcision/fructure in another comment would be a good study? The author there claimed they might not have been able to manage with defmacro, maybe someone familiar with both could articulate the challenges in detail. Is it just an issue of some things benefit a lot from pattern matching, and if so, does using CL's Trivia system mitigate that at all (in the same way that using gensym+packages+Lisp-2ness can mitigate hygiene issues)?

see also: fructure

Racket internalizes Extra-linguistic mechanisms https://felleisen.org/matthias/manifesto/sec_intern.html

Also the fact that various DSLs can inter-op with each other directly, so that you can use something like a binary parser description, as if it was just another Racket library. For example this description of the format https://github.com/Bogdanp/racket-binfmt/blob/master/binfmt-..., is directly included in another file as a regular library https://github.com/Bogdanp/racket-binfmt/blob/master/binfmt-...

I agree that startup time is not a winning aspect of Racket. My naive understanding is because Racket is not a direct bytecode interpreter like CPython, but actually has to run a compile step to native code, and doing that for programs + their required libraries necessarily takes at least a couple of hundred milliseconds even before anything can start running, while CPython can pretty much start executing from the get go.