1# Elixir
 2
 3Elixir support is available through the [Elixir extension](https://github.com/zed-industries/zed/tree/main/extensions/elixir).
 4
 5## Choosing a language server
 6
 7The Elixir extension offers language server support for `elixir-ls`, `next-ls`, and `lexical`.
 8
 9`elixir-ls` is enabled by default.
10
11To switch to `next-ls`, add the following to your `settings.json`:
12
13```json
14{
15  "languages": {
16    "Elixir": {
17      "language_servers": ["next-ls", "!elixir-ls", "..."]
18    }
19  }
20}
21```
22
23To switch to `lexical`, add the following to your `settings.json`:
24
25```json
26{
27  "languages": {
28    "Elixir": {
29      "language_servers": ["lexical", "!elixir-ls", "..."]
30    }
31  }
32}
33```
34
35## Setting up `elixir-ls`
36
371. Install `elixir`:
38
39```bash
40brew install elixir
41```
42
432. Install `elixir-ls`:
44
45```bash
46brew install elixir-ls
47```
48
493. Restart Zed
50
51> If `elixir-ls` is not running in an elixir project, check the error log via the command palette action `zed: open log`. If you find an error message mentioning: `invalid LSP message header "Shall I install Hex? (if running non-interactively, use \"mix local.hex --force\") [Yn]`, you might need to install [`Hex`](https://hex.pm). You run `elixir-ls` from the command line and accept the prompt to install `Hex`.
52
53### Formatting with Mix
54
55If you prefer to format your code with [Mix](https://hexdocs.pm/mix/Mix.html), use the following snippet in your `settings.json` file to configure it as an external formatter. Formatting will occur on file save.
56
57```json
58{
59  "languages": {
60    "Elixir": {
61      "format_on_save": {
62        "external": {
63          "command": "mix",
64          "arguments": ["format", "--stdin-filename", "{buffer_path}", "-"]
65        }
66      }
67    }
68  }
69}
70```
71
72### Additional workspace configuration options (requires Zed `0.128.0`):
73
74You can pass additional elixir-ls workspace configuration options via lsp settings in `settings.json`.
75
76The following example disables dialyzer:
77
78```json
79"lsp": {
80  "elixir-ls": {
81    "settings": {
82      "dialyzerEnabled": false
83    }
84  }
85}
86```
87
88See [ElixirLS configuration settings](https://github.com/elixir-lsp/elixir-ls#elixirls-configuration-settings) for more options.