Troubleshooting

Is something in Bevy not working as expected? Maybe one of these will resolve your problem:

Unable to find a GPU

thread 'main' panicked at 'Unable to find a GPU! Make sure you have installed required drivers!'

This error message means that bevy is unable to draw to your screen. Causes include:

1. Vulkan-compatible drivers not installed. To fix this, install/update the drivers. On Linux this may be vulkan-intel or vulkan-radeon.
2. Trying to run an example on a headless machine. To fix this, install a GPU!

Unable to debug dynamically linked Bevy application in VSCode on Windows

The program '[10184] my-game.exe' has exited with code -1073741515 (0xc0000135).

Whilst cargo run may load the application successfully, running via the debugging UI in VSCode may yield the above error. This error means that the required libraries were not loaded correctly (likely due to a pathing quirk with VSCode debug extensions on Windows).

Edit your launch configurations in .vscode/launch.json so that the rust libraries are found correctly.

For cppvsdbg:

"environment": [
    {"name":"PATH", "value":"%USERPROFILE%/.rustup/toolchains/nightly-x86_64-pc-windows-msvc/bin;${workspaceFolder}/target/debug/deps;%PATH%"}
    // Switch `nightly` to `stable` if you're using Rust stable
],

Or for codelldb:

"env": {
    "PATH": "${env:USERPROFILE}/.rustup/toolchains/nightly-x86_64-pc-windows-msvc/bin;${workspaceFolder}/target/debug/deps;${env:PATH}",
    // Switch `nightly` to `stable` if you're using Rust stable
},

Unable to compile getrandom when building for web

Bevy binaries tend to depend on getrandom through the uuid crate among others, and the standard getrandom implementation does not work for (some) web/wasm targets.

   Compiling getrandom v0.3.4
   Compiling getrandom v0.4.2
error: The wasm32-unknown-unknown targets are not supported by default; you may need to enable the "wasm_js" crate feature.

If you only had one tree dependency on getrandom, then adding getrandom = { version = "*", features = ["wasm_js"] } would solve the issue like getrandom suggests.

However, if your crate depends on multiple versions of getrandom (which it likely will indirectly), this will not be enough: The wildcard version pattern still ends up reflecting only a single version of the crate you want to add a feature for.

Going through cargo tree --invert getrandom you can find crates in your dependency tree that use getrandom (e.g. uuid and ahash), and figure out if they have a solution that applies the fix for you. This can feel a little indirect and fragile though, since you might notice that a lot of crates share the same getrandom version, and you just want that crate to change its implementation.

If you want to directly enforce a feature for multiple versions of a crate, you have to "rename" them. Cargo does not know that you want a feature to apply to every instance of the crate (what if a cargo feature only exists for some versions of the dependency?), so it has to be stated multiple times without creating a name conflict in your dependency table:

# in `Cargo.toml`:
[target.'cfg(all(target_family = "wasm", any(target_os = "unknown", target_os = "none")))'.dependencies]
getrandom_a = { package = "getrandom", version = "0.3.4", features = ["wasm_js"] }
getrandom_b = { package = "getrandom", version = "0.4.2", features = ["wasm_js"] }