Theme 1: Rust’s safety and concurrency advantages
- “fearless concurrency is another motivating factor. Better perf can be achieved by squeezing more parallelism, but without borrow checking it's difficult to do fine-grained parallelism correctly.” – pornel
- “Not having to worry about data races might give more confidence with trying out more complex techniques for how to split up work in a way that ends up making things faster.” – saghm
- “It's possible to write safe code in C or C++ but it's extremely difficult to read existing code and prove it's safe… The problem is not writing the code, it is continually verifying it.” – someonebaggy
Theme 2: Platform support / bootstrapping limitations of Rust
- “The main disadvantage of Rust right now is not supporting some more obscure platforms… GCC and therefore C/C++ supports some old stuff like SuperH, Intel Itanium, PA‑RISC and a bunch of microcontroller archs that LLVM does not.” – fotcorn
- “LLVM does not support as many backends as GCC does… there are many. Two big ones are Alpha and PA‑RISC.” – steveklabnik / bkallus
- “Rust is not actually the right tool for all problems… we will have to fork and maintain the c version as mold2 forever.” – lrvick
Theme 3: Use of AI‑assisted coding in the rewrite
- “IMO, given the recent commits: almost certainly.” – LoganDark (referring to AI tool use)
- “Assisted, yes. Claude is a coauthor for some of the commits and I think he also said that explicitly. Vibe‑coded, he claims not.” – afdbcreid
- “Was the conversion assisted? … Yes. Comment by mold's author: …” – dmit (citing the author’s confirmation)