[tazjin]

Flakes are a misfeature that adds a complicated layer of abstraction over an already not very simple system.

I follow some chats with lots of Nix beginners, and the amount of people that are now stuck in a flakes tarpit and have no understanding of the fundamentals of Nix (and no path to get there, really, in the course of normal usage) is depressing. Just the other day I saw someone post a 40 line Nix code snippet using flakes, pulling in 2 git repos apart from nixpkgs (because the barebones flakes are barely even usable without support libraries), all to make a simple nix-shell with a single package in there - and it didn't even work and they were unsure how to proceed with debugging.

In almost all chats with flakes proponents it also eventually turned out that what they want is something like niv, but integrated into the Nix binary, not all of the additional stuff that is attached to flakes.

Anyways, adisbladis' point is that Tvix does not need to support flakes in any way. If you really want to add these complications to your Nix code, you can implement everything flakes do in pure Nix (using e.g. the flakes-compat thing linked above).

[flurie]

Sure, and this is all fine, but it feels like this information gets buried or smoothed-over, and I think you strengthen your position by leading with it as a differentiator. Nobody new to Nix knows what targeting 2.3 means, but they likely know what flakes are, and you aren't doing a lot to make it clear why they should prefer a fast language evaluator to something that can handle flakes.