Helix

In your project root, put the following into your .helix/languages.toml:

[[language]]
name = "nix"
language-servers = ["devenv-lsp"]

[language-server.devenv-lsp]
command = "devenv"
args = ["lsp"]

This will make Helix use the devenv lsp for all Nix files.

Then enter devenv shell and run hx.

Most languages servers and code formatting tools provided by devenv are readily available to Helix, as it will just look for them in your $PATH.

To troubleshoot, inside your devenv shell, run hx --health [<language_name>]. This will print out which executables helix is configured to use for this language (or all languages known to Helix if no language_name is given), and which are correctly found.

For more information, have a look at the Helix doc about languages.