Configuration Reference

The following fields exist and can be configured:

• Configuration Reference
  • features
  • default-features
  • target
  • rustflags
  • wasm-opt
  • headers
  • unstable
    • unstable.web-multi-threading

features

• Type: array of strings
• Default: none
• Note: Which features to use.

default-features

• Type: boolean
• Default: true
• Note: Whether or not to use the default-features.

target

• Type: string
• Default: your host target triple for native builds, wasm32-unknown-unknown for web builds
• Note: To get a list of supported targets, run rustc --print target-list.

rustflags

• Type: string or array of strings
• Default: none
• Note: Extra command-line flags to pass to rustc. The value may be an array of strings or a space-separated string. Flags defined in the RUSTFLAGS environmental variable or .cargo/config.toml will be appended to this value.

wasm-opt

• Type: boolean or array of strings
• Default: true for web --release builds, false for web development builds and native builds
• Note: Whether or not to use wasm-opt to optimize the web binary. The specific flags to be used can be passed as array of strings or true can be passed to use default options (--strip-debug and -Os).

headers

• Type: array of strings
• Default: none
• Note: Headers may be in the format of KEY:VALUE or KEY=VALUE. These headers are appended to the defaults set by the HTTP server. For a list of supported values, please see MDN's docs on HTTP headers.

unstable

• Type: map
• Note: Enable unstable CLI features. Only available when building the CLI with the unstable feature (enabled by default).

unstable.web-multi-threading

• Type: boolean
• Default: false
• Note: Enable Wasm multi-threading features.