For somebody who hasn't used Nix yet, but heard good things about it, why use Tvix instead of Nix? The page didn't seem to mention the reason(s) behind the project.
The goals they list are:
> Creating an alternative implementation of Nix that is fully compatible with nixpkgs.
No explanation needed.
> More efficient Nix language evaluation, leading to greatly increased performance.
The Nix language is evaluated whenever doing the Nix equivalent of installing a package, or rebuilding your configuration. Note that most of the time it's "fast enough" but the authors of Tvix are doing more with the Nix language (which leads into)
> No more strict separation of evaluation and build phases: Generating Nix data structures from build artefacts ("IFD") should be supported first-class and not incur significant performance cost.
and
> Well-defined interaction protocols for how the three different components (evaluator, builder, store) interact.
As it currently works, the Nix language is evaluated to something called a derivation, which is a specific format for defining how to build something (including a list of dependencies). The derivation is then used to actually build the artifact. This is about when you want the metaphorical snake to eat its tail and have the results of a derivation be more nix language to evaluate.
> A builder implementation using OCI instead of custom sandboxing code.
Hermetic builds require some sandboxing; Using OCI containers seems like an obvious choice, but didn't exist when Nix was first created.
> Hermetic builds require some sandboxing; Using OCI containers seems like an obvious choice, but didn't exist when Nix was first created.
Presumably this would make this implementation Linux-only, since OCI isn't natively supported outside of Linux?
A complete non-starter, never in a thousand years am I gonna use something that requires a Docker installation for building derivations.
Using this for what Nix is doing is absolute madness. Docker is madness in general, but dragging it into Nix's core is madness cubed.
if you don't want docker-contributed code, here are some alternative implementations of the spec: https://github.com/opencontainers/runtime-spec/blob/main/imp... I believe nix could use one of these with some volunteer effort? Perhaps you could even be the one to purge the Docker heresy from the project!
It is an attempt at an open-source "just good enough" Docker clone.
You understand the difference?
huh?