It seems like this is more like writing Rust in an s-expression syntax instead of having a proper lisp dialect that compiles to Rust, which is cool I guess but not very interesting.
It's quite weird-looking for someone who's done any amount of lisp programming.
>Rust semantics with LISP syntax. A transparent s-expression frontend that compiles directly to Rust — no runtime, no GC
The first paragraph says literally that.
A let that defines variables that have a lifetime beyond the scope of the expression? Yeah, that's really unusual. And it's not even the oddest looking thing from the first example block of code.
Yeah, it sort of reminds me of the microcode assembly of a few of the lisp machines, that, while in s-expressions were also clearly not lisp themselves. But could be an interesting target for some lisp macros.