leptos VS devenv

Lots of new frontend frameworks have been built on top of Rust, including Leptos, which happens to be one of the most popular ones. In this guide, we'll highlight why and how to migrate your JavaScript frontend to use the Leptos Rust frontend framework.

I don't know why OP felt moved to write this weird guide, https://leptos.dev is incredible!

https://github.com/leptos-rs/leptos/blob/main/flake.nix

You want a package? Add it to buildInputs.

You want to search a package: https://search.nixos.org/packages (or use the cli)

you want to test a package before adding it? nix-shell -p or nix shell for example.

Heck, even if you want it more easy, you could write a tool in less than 100 lines that adds packages names to .json/.yaml/.toml, which allows you to parse it using the nix language and a simple cli written with bash functions to add/remove packages if you wanted.

That's why it is hard for me to understand this project as a product, it seems like a wrapper to the most basic things :\

We use the fantastic Leptos framework for building the frontend. Besides that, we use the leptos-use utilities for connecting to the WebSocket server, serde for serialization, and rand for generating random numbers.

I'd use https://leptos.dev because you can use a fully typed language (Rust) that is super fast in the backend and also in the frontend (see https://krausest.github.io/js-framework-benchmark/2024/table...)

For the web-side, if you'd like to use Rust end-to-end we've had the best experience with Leptos: https://leptos.dev/

I'd suggest https://leptos.dev/ is worth a look. I haven't used it yet, but plan to soon.

I think a lot of us reach for Jinja-style templates so it feels a little more like we're writing bare HTML. But they're of course still just templates, and they need a build step before they become valid HTML.

So it's true, if you're willing to use a DSL embedded in your server language (like JSX), then you'll have the full language tooling available to you. And this probably isn't giving up much over language-specific templates.

A JSX-equivalent for the Rust server-side rendering world would probably be maud [1] or leptops [2].

[1] https://github.com/lambda-fairy/maud

[2] https://github.com/leptos-rs/leptos

I wanted to deploy the app serverlessly, opting for Deno Deploy hosting. The JS fetch example and the leptos-deno examples were handy to get me going.

Sounds like nix using devenv[1] also would solve this problem.

https://devenv.sh/

It works on MacOS/Windows, unlike systemd. Therefore it's well suited for development environment setups for polyglot teams.

https://devenv.sh/ is one example that uses it to do just that.

I gave devenv multiple tries, and I am sorry to say there are multiple annoying issues that forced me to give up every time.

Some of these 200+ issues are unsolved for a fairly long time.

https://github.com/cachix/devenv/issues

Software developers often want to customize:

1. their home environments: for packages (some reach for brew on MacOS) and configurations (dotfiles, and some reach for stow).

2. their development shells: for build dependencies (compilers, SDKs, libraries), tools (LSP, linters, formatters, debuggers), and services (runtime, database). Some reach for devcontainers here.

3. or even their operating systems: for development, for CI, for deployment, or for personal use.

Nix provision all of the above in the same language, with Nixpkgs, NixOS, home-manager, and devShells such as https://devenv.sh/. What's more, Nix is (https://nixos.org/):

- reproducible: what works on your dev machine also works in CI in prod,

- declarative: you version control and review your configurations and infrastructure as code, at a reasonable level of abstraction,

- reliable: all changes are atomic with easy roll back.

https://devenv.sh/ and nix in general are great for setting up dev environments.

> but worried that the development is not moving forward

There is an open v1.0 PR: https://github.com/cachix/devenv/pull/1005

2) A way to run services apps depend on (databases, job runners, cache etc).

I am going to suggest one of the Nix based tools that do those things:

  - https://devenv.sh/ (I use this at work)

Yup, I haven’t tried it but there is https://devenv.sh which is built on top of nix and makes it simple.

Although Guix reads better than Nix (after all, it's Lisp), I found the support and resources available for learning severely lacking.

Plus, you have to jump through hoops to install non-free software, which goes against the ethos of Guix anyway.

IMHO, Nix is clearly "the winner" here and we'll see more and more adoption as it improves. Lots of folks are doing exciting work (see https://determinate.systems/, https://devenv.sh/, https://flakehub.com/). And the scale and organization around nixpkgs is damn impressive.

I don't think you can ever get Nix as simple as PNPM, simply because native libraries are sometimes annoying, need to be configured at build time to a greater degree and because the problem space it attacks is so much larger than PNPM, which only deals with the JS/Node.js ecosystem.

However, I do think that there exist reasonable levels of abstraction that sacrifice some expressive power for simplicity and such systems could maybe expose a PNPM-like CLI. One example that comes to mind is devenv.nix [1]. While it doesn't yet have a CLI, its configuration file is YAML and relatively simple. I think there's more to be done in this space and I hope for tools that are easier to grasp in the future.

> Nix package files evaluate down to configuration for the Nix package manager, but I haven’t ever seen a good explanation for the basic essentials underneath all the abstraction. Every guide I’ve learned from and all the package defs I’ve read seem to cargo cult many layers of mysterious config composing config. Without easy to learn essentials it’s difficult to grok the system as a whole.

To me it sounds like the essential that you're referring to is the 'derivation' primitive, which is almost always hidden behind the mkDerivation abstraction from nixpkgs. This [2] blog post is an exploration of what exactly that means.

I'd also love for the documentation situation to be much better, in particular in terms of official, curated resources. But I'm not convinced that you actually need to know the difference between derivation and mkDerivation to make effective use of Nix, because in practice you would always use the latter. That said, mkDerivation and the whole of nixpkgs is essentially a huge DSL (I believe this is what you meant when you said 'config composing config') that you do need to know and is woefully underdocumented.

> I would love to adopt Nix for developer tooling for Notion’s engineers, but today it’s about infinity times easier to work around the limitations mentioned of Docker+Ubuntu+NPM than to work around the limitations of Nix.

One approach I have taken to is to specify the environment in Nix, but then generate Docker devcontainers from it, so most people don't come into contact with Nix if they don't want to.

[1] https://devenv.sh

[2] https://ianthehenry.com/posts/how-to-learn-nix/derivations/