bevy_settings

A small framework for saving and loading user preferences.

Purpose

Most games need a place to persist user choices — graphics quality, key bindings, language, audio volume — that's separate from save data. bevy_settings provides a typed, reflected wrapper that loads on startup, watches for changes, and writes to a JSON/RON file.

Directory layout

crates/bevy_settings/src/
├── lib.rs        # SettingsPlugin
├── settings.rs   # Settings trait + storage
└── …

Key abstractions

Type	File	Description
SettingsPlugin<T>	crates/bevy_settings/src/lib.rs	Loads and saves a T: Settings resource.
Settings (trait)	crates/bevy_settings/src/settings.rs	Marker trait — Reflect + Resource + Default.

How it works

On startup, the plugin reads a per-platform user-preference path (via directories-crate logic or similar), deserializes the file, and inserts the value as a resource. A change-detection system watches the resource and writes back when it changes.

The actual file format is reflection-driven so any reflected struct can be a settings type.

Integration points

• Depends on: bevy_app, bevy_ecs, bevy_reflect, serde, directories or platform-specific.
• Depended on by: Apps that opt in.

Entry points for modification

• Custom storage path: SettingsPlugin::<T>::with_path.
• Custom format: add a saver trait alongside the existing serde-based one.

See also

• bevy_reflect — drives serialization.
• The examples/usage/settings.rs example demonstrates a typical use.