Show HN: (alter)native-Linux-builder for Nix on Darwin

A swift-based binary that can be used as an external builder for nix (via external-builders experimental feature) to build linux packages on darwin without having to setup a full remote build VM. This project aims to reproduce the functionality of Determinate Nix's native-linux-builder for upstream Nix installs. It also provides a Nix-darwin module to configure the external builder.