# Next LS
[](https://discord.gg/6XdGnxVA2A)
[](https://github.com/elixir-tools/next-ls/releases)
[](https://github.com/orgs/elixir-tools/discussions)
The language server for Elixir that just works. 😎
Still in heavy development, currently supporting the following features:
- Compiler Diagnostics
- Code Formatting
- Workspace Symbols
- Document Symbols
- Go To Definition
- Workspace Folders
- Find References
- Extensions
- Credo
## Editor Support
<ul>
<li>Neovim: <a href="https://github.com/elixir-tools/elixir-tools.nvim">elixir-tools.nvim</a></li>
<li>VSCode: <a href="https://github.com/elixir-tools/elixir-tools.vscode">elixir-tools.vscode</a></li>
<li>
<details>
<summary>Emacs</summary>
Using eglot:
```elisp
(require 'eglot)
(add-to-list 'exec-path "path/to/next-ls/bin/")
(with-eval-after-load 'eglot
(add-to-list 'eglot-server-programs
`((elixir-ts-mode heex-ts-mode elixir-mode) .
("nextls" "--stdio=true"))))
(add-hook 'elixir-mode-hook 'eglot-ensure)
(add-hook 'elixir-ts-mode-hook 'eglot-ensure)
(add-hook 'heex-ts-mode-hook 'eglot-ensure)
```
</details>
</li>
<li>
<details>
<summary>Helix</summary>
Add the following config to your `~/.config/helix/languages.toml`.
```toml
[[language]]
name = "elixir"
scope = "source.elixir"
language-server = { command = "path/to/next-ls", args = ["--stdio=true"] }
```
</details>
</li>
</ul>
## Installation
The preferred way to use Next LS is through one of the supported editor extensions.
If you need to install Next LS on it's own, you can download the appropriate executable from our [GitHub Releases](https://github.com/elixir-tools/next-ls/releases).
These executables are created with [Burrito](https://github.com/burrito-elixir/burrito) and are completely standalone, except you'll still need Elixir and OTP installed in order for it to start a runtime for your application code.
## Development
If you are making changes to Next LS and want to test them locally you can run `bin/start --port 9000` to start the language server (port 9000 is just an example, you can use any port that you want as long as it is not being used already).
Then you can configure your editor to connect to Next LS using that port.
[elixir-tools.nvim](https://github.com/elixir-tools/elixir-tools.nvim)
```lua
{
nextls = {enable = true, port = 9000}
}
```
Visual Studio Code
```json
{
"elixir-tools.nextls.adapter": "tcp",
"elixir-tools.nextls.port": 9000
}
```
### Note
Next LS creates an `.elixir-tools` hidden directory in your project, but it will be automatically ignored by `git`.
## Troubleshooting
### 1. Is `epmd` running?
#### Linux/Mac:
```bash
pgrep -fl epmd
```
If `epmd` is not running, you might need to start it or ensure it starts automatically with your system. You can do this by running `epmd -daemon`.
### 2. Ensure `glibc` version is at least 2.34
#### Linux:
```bash
ldd --version
```
This will show the `glibc` version at the top. Ensure it's 2.34 or higher.
#### Mac:
macOS doesn't use `glibc`; it uses the Darwin C Library. Hence, this step is not applicable.
#### Windows:
Windows does not use `glibc`. If you're using a subsystem or tool that needs it, ensure it's updated.
### 3. Open Visual Studio Code from the terminal
To ensure that `elixir` is in your `PATH`, open Visual Studio Code from the terminal using the [command-line tools](https://code.visualstudio.com/docs/editor/command-line#_launching-from-command-line).
### 4. Does it work in TCP mode?
#### All Platforms:
Start the language server in TCP mode and connect to it with your editor, as described above.
Both extensions install the Next LS executable to `~/.cache/elixir-tools/nextls/bin/nextls`, so you can start the server with `~/.cache/elixir-tools/nextls/bin/nextls --port 9000`.
### 5. Firewall Interference
Sometimes, the firewall can interfere with `epmd` and each Erlang node's ability to cluster. If you face connection issues, you might try turning off the firewall temporarily to see if it resolves the issue.
This is usually a problem on macOS, as you should see a popup asking if `beam` and `epmd` can accept incoming connections (which you should click "yes").
In future version, we plan to sign and notarize the darwin binaries, which should avoid this popups and make this a non-issue.
