Tweag + Nix dev update #15

// TODO: Insert some catchy introduction sentence linking to the previous update

Nix fuzzing

@pamplemousse kept working on the fuzzing of the Nix evaluator. You can read more about it here, but the gist of it is that we’re slowly approaching the point where we can run some full-scale fuzzing sessions.


  • Thanks to the intense work of @yannham and @garbas, the website is (at last) live: . Go check it out and play with the online repl. And enjoy the shiny new logo.

  • As part of this, @yannham found a small bug in the lexer, which turned out to have a rather complex fix because of a bug in the underlying lexing library (#363)

  • @ravendii and @yannham intensively discussed the design of the record overriding (#330).


  • @regnat wrote and @edolstra reviewed a number of fixes for some issues on the 2.4 milestone (3516, 3774, 3944 and 3503 which are merged, as well as #4548, #3888 and #4507 which are still WIP).
    There’s still a bunch of issues in the associated milestone, but it’s shrinking quickly, and only a handful of them are really critical anymore.
  • Thanks to the knowledge accumulated during his past work on the Nix evaluator (4154 and 4355), @infinisil started a Wiki page on the Nix evaluaton performance and the tradeofs to have in mind when writing performance-sensitive (!) Nix code.

And that’s all, folks