A Rust + WASM development environment with Nix
I was recently following the setup guide for Rust and WebAssembly and found more surprises than I was expecting while setting up the development environment using a Nix Flake. As I’ve also been working towards a personal repository of Flake templates, I thought it might help others to detail the issues that I encountered and how I solved them. It’s as much about the process of debugging a new Flake environment (and a new toolchain in general) as it is about the final state of the template!
This post assumes some basic familiarity with Nix and Flakes. I’m still relatively new to Nix, so if you notice anything in this post that you think is incorrect, please open an issue so that I can fix it.
If you already know what you’re doing and you’re here looking to get started without the more in-depth explanation, you should be able to use the rust-wasm-project template via github:jkaye2012/flake-templates#rust-wasm-project. More detailed instructions can be found in the last section of the post.
The first step in setting up a development environment is installing dependencies (surprise!). We need the Rust toolchain, wasm-pack (to build WebAssembly from Rust code), and npm (to manage web dependencies, build/run the site, etc). This is Nix, so dependency installation should be the easy part:
