hex-cmp

blink.cmp source for hex.pm package completion in Elixir mix.exs files.

Features

• Package name completion — search hex.pm as you type in the first position of a dep tuple
• Version completion — ~> fuzzy versions and exact versions, with retired versions marked
• Dependency opts completion — all Mix.Project dependency options (only:, git:, path:, etc.)
• Signature help — {app, requirement, opts} with full documentation
• Hover — package description, version, downloads, license, and links via K
• Disk cache — responses cached with TTL, stale cache served on API failure

Requirements

• Neovim >= 0.10
• blink.cmp
• tree-sitter-elixir parser
• curl on PATH

Installation

lazy.nvim

Add hex-cmp as a dependency of blink.cmp:

{
  'saghen/blink.cmp',
  dependencies = {
    'dbernheisel/hex-cmp',
  },
  opts = {
    sources = {
      per_filetype = {
        elixir = { inherit_defaults = true, 'hex' },
      },
      providers = {
        hex = { name = "hex", module = "hex_cmp", async = true },
      },
    },
  },
}

Hover

Add this to your LSP on_attach to get hex package info on lsp.hover
(typically mapped to K):

local bufname = vim.api.nvim_buf_get_name(bufnr)
if bufname:match('mix%.exs$') then
  require('hex_cmp.hover').attach(bufnr)
end

This starts a lightweight in-process LSP that only provides textDocument/hover. It works alongside your existing Elixir LSP — no keymap changes needed.

Configuration

Options can be passed via the provider opts:

hex = {
  name = "hex",
  module = "hex_cmp",
  async = true,
  opts = {
    cache_ttl = 1800,    -- seconds (default: 1800 - 30 minutes)
    max_results = 50,   -- max search results (default: 50)
  },
},

Health

Run :checkhealth hex_cmp to verify your setup.

How it works

hex-cmp uses treesitter to detect when the cursor is inside a defp deps (or def deps) function in mix.exs. Based on the cursor position within the dep tuple:

API responses are cached to disk at vim.fn.stdpath('cache') .. '/hex-cmp/' with a configurable TTL. Stale cache is served as a fallback when the API is unreachable.