After I saw the title, I thought "oh, it seems to kind of occupy the same space as esbuild, but for CSS. I wonder if the devs gave any thought to performance?" Then I clicked the link and saw that there a direct comparison with esbuild, with Parcel being 3x faster on a large real-world benchmark (Bootstrap 4).
This is really impressive. Although Rust tooling is rather suboptimal, Rust programs seems to have quite the performance edge. I'll take the RESF any day as long as it means getting away from ultra-heavy webtech everywhere.
The Rust compiler is both dog-slow and massive (both from a source and binaries perspective), and doesn't have a working incremental compilation mode yet, or support in-process hot-patching. There's no Rust REPL (hacks like papyrus don't count). Poor structural editing support. Integration with various editors/IDEs is lacking (e.g. there's no support for reporting possible performance issues with code constructs in any editor that I'm aware of, nor is there in-editor per-function disassembly or LLVM IR inspection, or borrow-checker lifetime annotation, no extract-function refactoring).
Cargo being good is necessary, but not sufficient.
This is really impressive. Although Rust tooling is rather suboptimal, Rust programs seems to have quite the performance edge. I'll take the RESF any day as long as it means getting away from ultra-heavy webtech everywhere.