Integrate Biome in an editor extension

Biome has LSP first-class support. If your editor does implement LSP, then the integration of Biome should be seamless.

Use the LSP proxy

Biome has a command called lsp-proxy. When executed, Biome will spawn two processes:

• a daemon that does execute the requested operations;
• a server that functions as a proxy between the requests of the client - the editor - and the server - the daemon;

If your editor is able to interact with a server and send JSON-RPC request, you only need to configure the editor run that command.

You can check how the neo-vim biome extension does it.

Use stdin

If your editor doesn’t support LSP, you use directly the binary biome and call it using standard input.

The following commands can be called via standard input:

• format
• lint
• check

Biome will return the new output (or the original output if changes haven’t occurred) to standard output and the diagnostics to standard error.

When you use stdin, you must pass the --stdin-file-path option. The file path doesn’t need to exist in your file system, it can be any name. What’s important is to provide the correct file extension, so Biome knows how to treat your file.

It’s the editor’s responsibility to locate the resolve the path of the binary and then call it when it’s needed. The binaries are shipped to npm based on the architectures and OS that we support:

• @biomejs/cli-darwin-arm64
• @biomejs/cli-darwin-x64
• @biomejs/cli-linux-arm64
• @biomejs/cli-linux-x64
• @biomejs/cli-win32-arm64
• @biomejs/cli-win32-x64

The binary name is biome or biome.exe, and it can be found in the root directory of the library, e.g.: @biomejs/cli-darwin-arm64/biome, @biomejs/cli-win32-x64/biome.exe.

Extension settings

The Biome Language Server exposes the following settings, which the extension can expose to users.

Note

The following settings are meant for extension developers, not for users. An extension might decide to expose the settings to users with different names, or different formats.

For example, the Zed extension maps the require_configuration setting from the setting require_config_file, which is defined in a JSONC file.

require_configuration

Type: boolean Default: false

Whether the Biome Language Server requires a configuration file. When set to true, it won’t analyze any file (except for parsing) until there’s a biome.json file in the root of the project.

{
  "require_configuration": true
}

configuration_path

Type: string Default: null

A path to a custom configuration file. The path can be the folder where the biome.json/biome.jsonc is, or a path to a file.

The path can be relative or absolute. The Biome Language Server reads this option only when provided. Use this option when the configuration is in a subfolder of your project.

{
  "configuration_path": "./frontend/biome.json"
}

inline_config

Type: object Default: null

An inline version of the Biome configuration. The options of this configuration will override the options coming from any biome.json file read from disk (or the defaults).

For example, let’s say your project enables the rule noConsole with error severity:

biome.json

{
  "linter": {
    "rules": {
      "suspicious": {
        "noConsole": "error"
      }
    }
  }
}

However, during local development, you want to disable this rule because it’s useful and you don’t want to see red squiggles. In your inline_config, you would write something like the following:

{
  "inline_config": {
    "linter": {
      "rules": {
        "suspicious": {
          "noConsole": "off"
        }
      }
    }
  }
}

Use the daemon with the binary

Using the binary via CLI is very efficient, although you won’t be able to provide logs to your users. The CLI allows you to bootstrap a daemon and then use the CLI commands through the daemon itself.

In order to do so, you first need to start a daemon process with the start command:

biome start

Then, every command needs to add the --use-server options, e.g.:

echo "console.log('')" | biome format --use-server --stdin-file-path=dummy.js

Note

If you decide to use the daemon, you’re also responsible to restart/kill the process with the stop command, to avoid having ghost processes.

Caution

Operations via the daemon are significantly slower than the CLI itself, so it’s advised to run operations only on single files.

Daemon logs

The Biome daemon saves logs in your file system. Logs are stored in a folder called biome-logs. The path of this folder changes based on your operative system:

• Linux: ~/.cache/biome;
• Windows: C:\Users\<UserName>\AppData\Local\biomejs\biome\cache
• macOS: /Users/<UserName>/Library/Caches/dev.biomejs.biome

For other operative systems, you can find the folder in the system’s temporary directory.

To obtain the precise path, execute the following command:

biome explain daemon-logs

The log files are rotated on an hourly basis.