rust-overlay VS asdf

I'm trying to understand overlays in order to make a proper rustup install (I've read that this overlay is the best way to go).

real-world example: https://github.com/oxalica/rust-overlay/blob/master/flake.nix

In this language context specifically, if one wanted to manage their workspace with Nix I would reach for Riff and/or oxalica/rust-overlay first, since they are deliberately more aware of Rust-specific nuance. In the latter's case it has compatibility paths with rustup-toolchain files as well, for allowing your peers who can't or won't adopt Nix to continue to feel like first-class participants in the project. Another alternative I don't have experience with would be nix-community/fenix.

p.s. I'm not sure if it's mentioned much of anywhere, but it'd be neat if there was a way to figure out the appropriate cargo from a rust-toolchain/rust-toolchain.toml if present, ala https://github.com/oxalica/rust-overlay. Funnily enough 95% of my development time is in Rust, but I don't actually have it installed globally, fun times being a NixOS user. I'd definitely make the argument that cargo is an external dependency!

Many of us have moved to https://github.com/oxalica/rust-overlay over Mozilla's overlay.

We added rust-overlay, so we can easily specify different rust versions without relying on nixpkgs to give us what ever rust version in there.

If it's Rust, you can use https://github.com/oxalica/rust-overlay to get any version you want very easily without pinning an instance of nixpkgs just for it.

asdf does not allow you to keep three different versions of the same language, so I'm not sure how that compares? It's not super-trivial to do in Nix, but at least you can do it.

asdf is also no different than Nix when it comes to minor/major versions. You're at the mercy of what the plugin does, other than that you have to create your own plugin from scratch or make a fork. Nix has the option to patch things up more easily at least.

How does this compare to https://github.com/oxalica/rust-overlay/ ? Can fenix ingest a rust-toolchain file and provide packages from it?

Can you say a bit about how this compares to oxalica’s rust overlay?

I frequently try to do something, say use (from the README of rust overlay):

The main issue most people have with asdf is that it’s annoyingly slow. Not unusably so, but just enough that it’s irritating.

I identified [0] the source for much of it (sub-shells and pipes) and began a PR [1], but became bogged down with BATS testing, and then found mise / rtx, so kind of lost interest. Sorry. You can always implement these if you’d like.

[0]: https://github.com/asdf-vm/asdf/issues/290#issuecomment-1383...

[1]: https://github.com/asdf-vm/asdf/pull/1441

Or if you need to manage more than just node, asdf has been around for over a decade and works great. You can use a .tool-versions to change runtimes for each project you have, in addition to managing your global runtime versions

https://asdf-vm.com/

Why not just use a tool like asdf (https://asdf-vm.com/) or mise (https://mise.jdx.dev/)?

These tools have the advantage of not being multi-taskers and can manage version for all your tools. You wouldn’t need pyenv and npm and rvm and…

We’ve even started committing the .mise.toml files for projects to our repos. That way, since we work on multiple projects that may need multiple versions of the same tool, it’s handled and documented.

The purpose of a version manager is to help you navigate or install any tools for development easily. Version Manager can be one tool for each dependency (e.g. NVM, g) or One tool for all dependencies (e.g. asdf, mise).

(asdf)[https://asdf-vm.com/] fully supports Python and almost any other language. I've been using it for Ruby, Python, Elixir, and other languages for years and never looked back.

Secondly, our development environments must not drift, because then code may behave differently and a change could pass on our machine but fail in production. There are many tools for locking down environments, e.g nix, pkgx, asdf, containers, etc., and they all share the common goal of being able to lock down dependencies for an environment accurately and deterministically. And that needs to be enforced in our local workflow so we don't have to rely on CI environments for correctness. All developers must have environments that are effectively identical to what runs in CI (which itself should be representative of the production environment).

There are many ways this can be done (e.g nix, pkgx, asdf, containers, etc.), and we won’t get into which specific tools to use, because we'll instead cover the essential essence of preventing environment drift: