Layered, validated configuration conventions for Baukit services.

[ConfigLoader] applies configuration in this order: serde-backed defaults, an optional local file, then environment variables. Environment variables use an application prefix and a double-underscore separator, such as MYAPP__HTTP__PORT=8080. A local .env file is loaded only when the loader's deployment [Environment] is [Environment::Local]. Collection-valued environment variables use JSON array syntax, for example MYAPP__HTTP__CORS_ALLOWED_ORIGINS=["https://app.example.com"]. Scalar environment values retain their exact source strings, including values that look numeric, so secret-string preservation is unchanged. http.cors_allowed_origins is registered automatically; product collection fields must be declared with [ConfigLoader::environment_collection].

Durations in the standard sections are represented as [Duration] values and deserialize from integer seconds.

Shared environment and log-format vocabulary lives in the dependency-light baukit-core crate and is re-exported here. This lets configuration and telemetry use identical types without making configuration depend on the OpenTelemetry exporter stack.

Example

use baukit_config::{BaukitConfig, ConfigLoader, Environment, Validate, ValidationErrors};
use serde::Deserialize;

#[derive(Debug, Default, Deserialize)]
#[serde(default)]
struct ProductConfig {
    feature_name: Option<String>,
}

impl Validate for ProductConfig {
    fn validate(&self) -> Result<(), ValidationErrors> {
        Ok(())
    }
}

let config: BaukitConfig<ProductConfig> =
    ConfigLoader::new("myapp", Environment::Local)?.load()?;
# Ok::<(), baukit_config::LoadError>(())

baukit-config 0.1.0

Example