Crate clapfig 

Rich, layered configuration for Rust CLI apps.

Clapfig orchestrates configuration from multiple sources — config files, environment variables, and CLI flags — with a builder API. Built on confique for struct-driven defaults and template generation.

Three axes of configuration

Config file handling is controlled by three orthogonal settings on the builder:

• Discovery (search_paths()): where to look for config files. Supports explicit directories, platform paths, and walking up the directory tree via SearchPath::Ancestors.

• Resolution (search_mode()): what to do with found files. Merge deep-merges all found configs (layered overrides); FirstMatch uses only the highest-priority file found (“find my config”).

• Persistence (persist_path()): where config set writes. Explicit and independent of the search paths — no guessing.

See the types module for the full conceptual documentation and use-case examples.

Layer precedence (lowest to highest)

1. Compiled defaults (#[config(default = ...)])
2. Config files (discovery + resolution mode)
3. Environment variables (PREFIX__KEY)
4. CLI overrides (.cli_override())

Every layer is sparse — only the keys you specify are merged.

Quick start

let config: AppConfig = Clapfig::builder()
    .app_name("myapp")
    .load()?;

Re-exports

pub use error::ClapfigError;

pub use types::Boundary;

pub use types::ConfigAction;

pub use types::SearchMode;

pub use types::SearchPath;

Modules

error

types

Core types that define how clapfig discovers, resolves, and persists configuration.

Structs

Clapfig

Entry point for building a clapfig configuration.

ClapfigBuilder

Builder for configuring and loading layered configuration.

ConfigArgs

Clap-derived args for the config subcommand group.

Enums

ConfigResult

Result of a config operation. Returned to the caller for display.

ConfigSubcommand

Available config subcommands.