Bevy Cargo Features

Bevy 0.18 — Cargo features

When to use this skill

• Authoring or auditing a Bevy project's Cargo.toml.
• Trimming the WASM bundle (the single biggest lever).
• Building a headless server (no rendering, no windowing, no audio).
• Writing a custom renderer that needs Bevy's data types but not its render pipeline.
• Migrating from a 0.17 manifest — several features were renamed in 0.18.

Canonical patterns

High-level: pick one of the three "app shape" collections

# 3D game (default for most projects)
[dependencies]
bevy = { version = "0.18", features = ["3d"] }

# 2D-only game
[dependencies]
bevy = { version = "0.18", features = ["2d"] }

# UI-only tool (no scene rendering)
[dependencies]
bevy = { version = "0.18", features = ["ui"] }

2d, 3d, ui are the three top-level feature collections new in 0.18. They turn on a curated stack appropriate for that app shape. Use these instead of hand-picking 40 individual flags.

Mid-level: API without the default renderer

# I want Bevy's 3D component types and shading hooks,
# but I'm bringing my own render pipeline.
[dependencies]
bevy = { version = "0.18", default-features = false, features = ["3d_api"] }

2d_api, 3d_api, ui_api enable the API surface (component types, asset types, shader types) without enabling the high-level renderer plugins. New in 0.18.

Headless server

[dependencies]
# No rendering, no windowing, no audio — just ECS + assets + scenes.
bevy = { version = "0.18", default-features = false, features = [
    "bevy_scene",
    "bevy_asset",
    "serialize",
    "multi_threaded",
] }

Combine with MinimalPlugins (not DefaultPlugins) at runtime.

Minimal client, opt-in input

[dependencies]
bevy = { version = "0.18", default-features = false, features = [
    "3d_api",
    "x11",         # or "wayland", "windows", "macos"
    "mouse",
    "keyboard",
    "gamepad",
    # touch, gestures — add only if needed
] }

In 0.18, default-features = false no longer turns on input by default. Opt in to mouse, keyboard, gamepad, touch, gestures individually.

Feature renames (0.17 → 0.18)

| 0.17 name | 0.18 name | |---|---| | animation | gltf_animation | | bevy_sprite_picking_backend | sprite_picking | | bevy_ui_picking_backend | ui_picking | | bevy_mesh_picking_backend | mesh_picking | | documentation | reflect_documentation |

CI for a 0.17 → 0.18 upgrade should grep Cargo.toml for the left column.

WASM-specific advice

# In your client crate's Cargo.toml:
[dependencies]
bevy = { version = "0.18", default-features = false, features = [
    "3d_api",          # not "3d" — drop the default renderer
    "bevy_winit",      # window/event loop
    "webgl2",          # default browser backend; add "webgpu" if you also want it
    "mouse",
    "keyboard",
    "touch",           # mobile browsers
] }

[profile.wasm-release]
inherits = "release"
opt-level = "z"        # size, not speed
lto = "fat"
codegen-units = 1
strip = "debuginfo"

Bundle size targets: a stripped wasm-opt -Oz release should fit in 5–10 MB for a moderately-featured 3D client. If your bundle is >20 MB, the most common cause is leaving default-features = true.

Gotchas (0.18)

• default-features = true (or omitted) enables ~30 features. That's fine for desktop dev, fatal for WASM. Always explicit-feature WASM builds.
• Dev-vs-release feature split. A common pattern is [features] dev = ["bevy/dynamic_linking", "bevy/file_watcher", "bevy/embedded_watcher"] and only enable dev in cargo run, not cargo build --release.
• bevy_dev_tools (FPS overlay, system diagnostics) is its own feature — add it in dev and gate the plugin behind #[cfg(feature = "bevy_dev_tools")].
• multi_threaded is a separate Bevy feature in 0.18. On by default through the high-level collections; off in headless minimal builds unless you ask for it.
• trace_tracy / trace_chrome are mutually exclusive — picking both at once will pick one and silently ignore the other.
• Platform features (x11, wayland, windows, macos, android, ios) — at most one per target. Bevy will pick a sensible default if you don't, but for WASM you need bevy_winit and a web backend (webgl2 or webgpu).

See also

• bevy-wasm-webgpu — the WASM-specific story for picking a graphics backend.
• bevy-migration-0-17-to-0-18 — full feature-rename table and default-features change.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: chrisgliddon
• Source: chrisgliddon/bevy-skills
• License: MIT

Install and usage instructions live in the source repository linked above.