Incremental Builds

If your crate uses the embedded, Dioxus, or Bevy manager macros, they discover locales at compile time by scanning your assets_dir. By default, Cargo doesn’t know about these files, so changes like renaming a locale folder (e.g., fr → fr-FR) won’t trigger a rebuild.

The es-fluent-build crate provides a build.rs helper that emits cargo:rerun-if-changed directives for your locale assets, ensuring Cargo rebuilds when translations change. Crates that only use the derive macros do not need this setup.

Setup

Add es-fluent-build to your build dependencies:

[build-dependencies]
es-fluent-build = "0.16"

Call the tracking helper from build.rs:

// build.rs
fn main() {
    es_fluent_build::track_i18n_assets();
}

This guarantees your project recompiles whenever locale files or folders are added, removed, or renamed.