Neovim

Neovim is a highly extensible and open source text editor that aims to improve upon and modernize the popular Vim editor. It's designed to be a drop-in replacement for Vim, maintaining compatibility with most Vim plugins and configurations while offering additional features and improvements. Neovim focuses on extensibility, usability, and performance.

It introduces a powerful plugin architecture that allows for asynchronous plugin execution, which can significantly improve performance for certain operations. It also includes a built-in terminal emulator, allowing users to run shell commands directly within the editor. The project emphasizes code quality and maintainability, with a clean, well-documented codebase that makes it easier for developers to contribute.

Installation

Using nix-shell

nix-shell -p neovim

Using Global Configuration

environment.systemPackages = [
  pkgs.neovim
];

After modifying your configuration, apply the changes by running:

sudo nixos-rebuild switch

Using Home Configuration

home.packages = [ 
  pkgs.neovim 
];

After updating your configuration, apply the changes by running:

home-manager switch

Configuration

Basic

# Global Configuration
programs.neovim = {
   enable = true;
   defaultEditor = true;
};

# Home Configuration
programs.neovim = {
  enable = true;
  extraConfig = ''
    set number relativenumber
  '';
};

Advanced

# Global Configuration
programs.neovim = {
  enable = true;
  defaultEditor = true;
  viAlias = true;
  vimAlias = true;
  configure = {
    customRC = ''
      set number
      set cc=80
      set list
      set listchars=tab:→\ ,space:·,nbsp:␣,trail:•,eol:¶,precedes:«,extends:»
      if &diff
        colorscheme blue
      endif
    '';
    packages.myVimPackage = with pkgs.vimPlugins; {
      start = [ ctrlp ];
    };
  };
};

# Home Configuration
# You have to add the line below to set it as the default editor:
environment.variables.EDITOR = "nvim";

Tips and Tricks

Location of Options

The home manager options are defined in the following Home Manager Options Manual.

The global options are listed on MyNixOS.

Neovim Nightly

Have a look at the Neovim Nightly Overlay to install the most recent current nightly version of Neovim.

You can run the master version via the following command:

nix run "github:nix-community/neovim-nightly-overlay"

Pre-Configured Configurations

If you prefer not to configure your system manually, NixOS offers several predefined configurations and community-supported options. Here are a few of them:

Another excellent option is LunarVim. The development community describes it as "an IDE layer for Neovim with sane defaults." LunarVim includes an installer/updater for LSP modules and other features. It can be installed via the lunarvim package from nixpkgs and is started with the lvim command.

The configuration for LunarVim is stored in ./config/lvim.

Plugin Management

plugins = [
  # Example Plugin: nvim-tree-lua
  pkgs.vimPlugins.nvim-tree-lua

  # Example Plugin: vim-startify with configuration
  {
    plugin = pkgs.vimPlugins.vim-startify;
    config = "let g:startify_change_to_vcs_root = 0";
  }

  # Example Plugin: nvim-colorizer-lua with Lua config
  # Due to how the runtimepath for Lua modules is processed, your configuration may require 
  # packadd! plugin-name to require a module. A home-manager example:
  {
    plugin = pkgs.vimPlugins.nvim-colorizer-lua;
    config = ''
      packadd! nvim-colorizer.lua
      lua << END
        require 'colorizer'.setup {
          '*'; -- Highlight all files, but customize some others.
          '!vim'; -- Exclude vim from highlighting.
        }
      END
    '';
  }

  # Example Plugin: nvim-treesitter with Lua config
  {
    plugin = pkgs.vimPlugins.nvim-treesitter;
    config = ''
      packadd! nvim-treesitter
      lua <<EOF
        require'nvim-treesitter.configs'.setup {
          highlight = {
            enable = true,              -- false will disable the whole extension
            disable = {},               -- list of languages that will be disabled
          },
          incremental_selection = {
            enable = true,
            keymaps = {
              init_selection = "gnn",
              node_incremental = "grn",
              scope_incremental = "grc",
              node_decremental = "grm",
            },
          },
          textobjects = {
            select = {
              enable = true,
              lookahead = true,
              keymaps = {
                ["af"] = "@function.outer",
                ["if"] = "@function.inner",
                ["ac"] = "@class.outer",
                ["ic"] = "@class.inner",
              },
            },
          },
        }
      EOF
    '';
  }

  # Installing grammars for tree-sitter
  # Option 1: Install all grammar packages
  pkgs.vimPlugins.nvim-treesitter.withAllGrammars
  
  # Option 2: Install specific grammar packages
  # (pkgs.vimPlugins.nvim-treesitter.withPlugins (p: [ p.c p.java ]))

  # Option 3: Installing grammars without Nix
  # Installing grammar packages through the built-in command can lead to errors. 
  # The following Neovim command will install syntax highlighting for the C programming language: :TSInstall c
];

References