How to actually use a different treesitter grammar for nix?

[theutz]

I want to use a fork of the nix-community/tree-sitter-nix package, because I'm annoyed about the syntax errors when using pipe operators. But I cannot for the life of me figure out how to get it to work with a home-manager/flake-based setup.

Here's a minimal snippet of what I've got:

flake.nix

{ inputs = { tree-sitter-nix.url = "github:molybdenumsoftware/tree-sitter-nix"; } }

home.nix

{ inputs, ... }:
{ config.programs.nvf.settings.vim.languages.treesitter.package = inputs.tree-sitter-nix.packages.aarch64-darwin.default; }

---

When I set it up this way, my flake evaluates, but can't properly build the plugin. It gives the following error:

ERROR: runPhase: grammar version (0.3.0-unstable-2025-12-03) differs from source

But if I build the package directly with nix build, things work fine. Any ideas?