zmij

https://github.com/vitaut/zmij/commit/26b4aae7771c52314465d7... It is three months old, probably created after they submitted for publication.

zmij[1] is claimed to be significantly faster than all of the tested implementations in the paper. It would have been nice if it was included. [1] https://github.com/vitaut/zmij

The shortest double-to-string algorithm is basically Schubfach or, rather, it's variation Tejú Jaguá with digit output from Dragonbox. Schubfach is a beautiful algorithm: I implemented and wrote about it in https://vitaut.net/posts/2025/smallest-dtoa/. However, in terms of performance you can do much better nowadays. For example, https://github.com/vitaut/zmij does 1 instead of 2-3 costly 128x64-bit multiplications in the common case and has much more efficient digit output.

It's easier to write faster code in a language with compile-time facilities such as C++ or Rust than in C. For example, doing this sort of platform-specific optimization in C is a nightmare https://github.com/vitaut/zmij/blob/91f07497a3f6e2fb3a9f999a... (likely impossible without an external pass to generate multiple lookup tables).

I started a section to list implementations in other languages: https://github.com/vitaut/zmij?tab=readme-ov-file#other-lang.... Once yours is complete feel free to submit a PR to add it there.

I've added a C implementation in https://github.com/vitaut/zmij/blob/main/zmij.c in case you are interested.