hydra VS flake-utils-plus

See https://github.com/NixOS/hydra/issues/838 for making content-addressed derivations supported by hydra.nixos.org. At that point, we can actually try out the XP feature at scale.

Also see https://github.com/NixOS/nix/issues/8919 for this accepted RFC

Once those things are done, we can get back to merging in the IPFS code.

Now that there is an Nix team and I am on it, there is much, much less of an issue of these experiments being caught in limbo :).

https://github.com/nix-community/infra, Community project builds https://github.com/NixOS/hydra, NixOS build server

Nix is pretty cool, and I would say comparisons to Earthly are apt. I may tackle that in a follow-up. If you did a monorepo setup written in nix and then used something like Hydra for building, it might be a pretty nice solution.

Nix seems great for build servers. This is a great introduction to the motivations behind it.

I'm not sold on using it for managing developer environments (another use case it is often used for). It "solves" the problem that developers might be using different versions of libraries or compilers on their machines... but it comes at the cost of having to learn a whole new programming language, a configuration language, a whole new jargon, and workflow. It's a bit like using Docker as a development environment. It introduces a non-trivial amount of friction.

Some folks get excited about package management and configuration. Personally I don't care for it enough to over-come such a high learning curve. And I don't particularly like the workflow it enforces.

However it is pretty great for reproducible CI/CD systems like Hydra: https://github.com/NixOS/hydra

Somewhat related to this, is there a good way to install something from a flake inside the configuration.nix? For example, the hydra flake, since it includes many derivations for dependencies that are not part of nixpkgs (or are at the wrong versions).

You don't need channels to use nix-shell or nix-env. You can generate the Nix path and registry from your flake inputs. flake-utils-plus makes this easy with nix.generateRegistryFromInputs and nix.generateNixPathFromInputs.

Use flake-utils-plus to easily define multiple systems in flake.nix.and then use the --target-host flag of nixos-rebuild to deploy it remotely.

If you're trying to handle multiple systems with one config a flake is a significantly better option. I would personally recommend looking at flake-utils-plus and specifically this example config.

I looked at some past threads / examples and saw people recommend flake-utils-plus, but after reading the examples I don't understand how I would get home-manager on Darwin or Ubuntu.

Depending on your specific needs, the channelsConfig (modify arguments passed to Nixpkgs) and overlay tooling in flake-utils-plus may be adequate: https://github.com/gytis-ivaskevicius/flake-utils-plus/tree/...

For flakes you don't have to set up everything manually there are helper libraries, I use flake-utils-plus.

Converting to flakes is not that hard if you use a good library. The documentation is other people's configs, really.

Neat! I've been using flake-utils-plus's implementation until now. https://github.com/gytis-ivaskevicius/flake-utils-plus/blob/master/lib/repl.nix

I use flake-utils-plus based configuration to apply patches on top of nixpkgs where overlays don't suffice.