Regiux: prototyping a fast Nix interpreter (lixcon2026)

The Nix expression language is challenging to evaluate due to non-strict semantics, dynamic scoping, a diverse collection of builtin operators, and tight integration with the Nix store. We give a progress report on Regiux, an interpreter for Nix which is narrowly focused on efficient evaluation of expressions. Regiux is yet another attempt at a fast Nix evaluator. Come learn about the ingredients that go into modern compilers and interpreters, particularly: * Lexing and parsing * Desugaring and expanding * Intermediate languages for lambda calculus * Using the RPython JIT toolkit * Bytecode for lazy graph evaluation Licensed to the public under http://creativecommons.org/licenses/by/4.0 about this event: https://pretalx.dgnum.eu/lixcon-2026/talk/F83VYV/