Crate rtb_assets 

Embedded-asset + overlay filesystem abstraction.

Tools built on RTB ship assets from three places: compiled into the binary via rust_embed, on the user’s disk (per-user overrides), and in-memory (tests, scaffolders). Assets unifies these behind a single read-only API.

Semantics

• Binary reads (Assets::open, Assets::open_text, Assets::exists) follow last-wins shadowing. The highest-priority layer that provides the path supplies the bytes.
• Directory listing (Assets::list_dir) unions entries across layers, deduplicated and sorted.
• Structured merge (Assets::load_merged_yaml, Assets::load_merged_json) reads the file from every layer that has it and deep-merges via RFC-7396 merge-patch semantics — nested maps merge recursively; scalars replace wholesale.

Construction

use rtb_assets::Assets;
use std::collections::HashMap;

let assets = Assets::builder()
    .memory(
        "defaults",
        HashMap::from([("greeting.txt".into(), b"hello".to_vec())]),
    )
    .build();

assert_eq!(assets.open_text("greeting.txt").unwrap(), "hello");

See docs/development/specs/2026-04-22-rtb-assets-v0.1.md for the authoritative contract.

Re-exports

pub use assets::Assets;

pub use assets::AssetsBuilder;

pub use error::AssetError;

pub use source::AssetSource;

pub use source::DirectorySource;

pub use source::EmbeddedSource;

pub use source::MemorySource;

Modules

assets

The Assets overlay container and its AssetsBuilder.

error

Typed errors for the asset subsystem.

source

The AssetSource trait and its three built-in implementations.