How to enable syntax highlighting?

[rxtsel]

How to enable syntax highlighting?

Hi! I'm trying to get syntax highlighting to work in Svelte, Astro, TSX, etc files using NVF (configured declaratively via Home Manager in flakes). I’ve followed the docs and tried multiple approaches, but syntax highlighting does not activate.

My configuration looks like this:

syntaxHighlighting = true;

treesitter = {
  enable = true;
  fold = true;
  highlight.enable = true;
};

languages = {
  enableTreesitter = true;

  rust.enable = true;
  nix.enable = true;
  astro.enable = true;
  lua.enable = true;
  css.enable = true;
  tailwind.enable = true;

  svelte = {
    enable = true;
    format.enable = true;
    lsp.enable = true;
    treesitter.enable = true;
  };

  ts = {
    enable = true;
    extensions.ts-error-translator.enable = true;
  };

  markdown = {
    enable = true;
    extensions.markview-nvim.enable = true;
  };
};

I also tried these alternatives for installing parsers explicitly:

treesitter.grammars = with pkgs.vimPlugins.nvim-treesitter.builtGrammars; [
  svelte
];

And even:

treesitter.grammars = pkgs.vimPlugins.nvim-treesitter.allGrammars;

---

The problem

When I open a .svelte file:

• :set filetype? returns filetype=svelte
• :set syntax? returns syntax= → this is empty
• There is no syntax highlighting

Tree-sitter highlighting does work correctly in other filetypes like rust, nix, etc.

---

What I’d like to know

• Is this a bug in the current NVF setup or modules?
• Is there any additional configuration required to load the grammar and enable highlighting for Svelte?
• Is nvim-treesitter guaranteed to be loaded with the treesitter.enable = true flag?

Thanks in advance!

[NotAShelf]

Is this a bug in the current NVF setup or modules?

No, this is a bug in Nixpkgs' Treesitter packaging that should be addressed in recent Nixpkgs commits. Ensure that your Nixpkgs is up to date.

Is there any additional configuration required to load the grammar and enable highlighting for Svelte?

Besides languages.svelte.enable, no. The purpose of the language modules is to load everything necessary.

Is nvim-treesitter guaranteed to be loaded with the treesitter.enable = true flag?

Yes.

The treesitter setup is a little finnicky atm due to the upstream changes that made using nvim-treesitter annoying. Right now there's a mess caused by Nixpkgs mismatches, but letting NVF use its own Nixpkgs (i.e., no inputs.nixpkgs.follows) should provide the correct highlights. In my setup Nixpkgs is relatively up to date, so the grammar packaging is fixed and Svelte works as intended again.

[rxtsel]

Thanks a lot! That was the issue.

I previously had in my flake.nix:

nvf = {
  url = "github:NotAShelf/nvf";
  inputs.nixpkgs.follows = "nixpkgs";
};

Now I changed it to:

nvf = {
  url = "github:NotAShelf/nvf";
};

Then I ran:

nix flake update
sudo nixos-rebuild switch --flake ~/.dot/#blackout

And that fixed the problem — syntax highlighting works correctly in Svelte files now.
Really appreciate the help! ✨