Optional Dependencies

lde supports optional dependencies that are only installed when a specific feature flag is enabled. This is useful for platform-specific dependencies or add-ons that not every user of your package needs.

Adding Optional Dependencies

Add an "optional" field to any dependency in your lde.json:

"dependencies": {
  "winapi": { "git": "https://github.com/example/winapi", "optional": true }
}

Defining features

Features are named groups of optional dependencies. You define them under the "features" key in lde.json, where each key is a feature name and the value is a list of dependency names to enable:

"dependencies": {
  "winapi": { "git": "https://github.com/example/winapi", "optional": true },
  "luaposix": { "luarocks": "luaposix", "optional": true }
},
"features": {
  "windows": ["winapi"],
  "linux": ["luaposix"],
  "macos": ["luaposix"]
}

Built-in features

lde automatically activates one of the following feature flags based on the current operating system:

This means you can gate dependencies by OS without any extra configuration: just name your feature "windows", "linux", or "macos" and lde will activate the right one automatically.

Enabling Features

The features you define are for your own package. When you depend on a package that defines features of its own, you opt into them per dependency by adding a "features" key to its entry in your lde.json:

"dependencies": {
  "my-package": {
    "git": "https://github.com/example/my-package",
    "features": ["windows", "sdl2"]
  }
}