Neovim

The official LUMOS plugin for Neovim provides syntax highlighting via Tree-sitter and full LSP integration.

Installation

Using lazy.nvim (Recommended)

{
  "getlumos/nvim-lumos",
  dependencies = {
    "nvim-treesitter/nvim-treesitter",
    "neovim/nvim-lspconfig",
  },
  config = function()
    require("lumos").setup()
  end,
}

Using packer.nvim

use {
  "getlumos/nvim-lumos",
  requires = {
    "nvim-treesitter/nvim-treesitter",
    "neovim/nvim-lspconfig",
  },
  config = function()
    require("lumos").setup()
  end,
}

Manual Installation

# Clone to your plugins directory
git clone https://github.com/getlumos/nvim-lumos \
  ~/.local/share/nvim/site/pack/plugins/start/nvim-lumos

# Install Tree-sitter grammar
:TSInstall lumos

Requirements

Neovim 0.9+ (required)
nvim-treesitter - For syntax highlighting
nvim-lspconfig - For LSP features
lumos-lsp - LSP server
Terminal window
```
cargo install lumos-lsp
```

Features

Syntax Highlighting

Tree-sitter-based syntax highlighting for:

Keywords, types, and attributes
Comments (line and block)
String literals and numbers
Enum variants

LSP Integration

Full Language Server Protocol support:

Real-time diagnostics
Auto-completion
Hover documentation
Go to definition
Find references
Code actions

Pre-configured Keybindings

Key	Action
`gd`	Go to definition
`K`	Hover documentation
`gr`	Find references
`<leader>rn`	Rename symbol
`<leader>ca`	Code actions
`<leader>f`	Format document

Configuration

Basic Setup

require("lumos").setup({
  -- LSP server path (auto-detected if on PATH)
  lsp_cmd = { "lumos-lsp" },

  -- Enable diagnostics
  diagnostics = true,

  -- Format on save
  format_on_save = true,
})

Advanced Configuration

require("lumos").setup({
  lsp_cmd = { "lumos-lsp" },

  -- Custom keybindings
  on_attach = function(client, bufnr)
    local opts = { buffer = bufnr }

    vim.keymap.set("n", "gd", vim.lsp.buf.definition, opts)
    vim.keymap.set("n", "K", vim.lsp.buf.hover, opts)
    vim.keymap.set("n", "<leader>rn", vim.lsp.buf.rename, opts)
    vim.keymap.set("n", "<leader>ca", vim.lsp.buf.code_action, opts)
    vim.keymap.set("n", "gr", vim.lsp.buf.references, opts)
    vim.keymap.set("n", "<leader>f", function()
      vim.lsp.buf.format({ async = true })
    end, opts)
  end,

  -- Custom capabilities (for nvim-cmp integration)
  capabilities = require("cmp_nvim_lsp").default_capabilities(),
})

Integration with nvim-cmp

local cmp = require("cmp")

cmp.setup({
  sources = cmp.config.sources({
    { name = "nvim_lsp" },  -- LUMOS completions
    { name = "buffer" },
    { name = "path" },
  }),
})

Troubleshooting

LSP not starting

Verify lumos-lsp is installed:
Terminal window
```
lumos-lsp --version
```
Check LSP logs:
```
:LspLog
```
Manually start LSP:
```
:LspStart lumos
```

Tree-sitter not highlighting

Verify grammar is installed:
```
:TSInstallInfo lumos
```
Reinstall grammar:
```
:TSInstall lumos
```

File type not detected

Add to your config:

vim.filetype.add({
  extension = {
    lumos = "lumos",
  },
})