facet-postcard

facet-postcard

Postcard serialization and deserialization for Facet types.

Postcard is a compact, efficient binary serialization format designed for embedded and no_std environments. This crate provides byte-for-byte compatible output with the standard postcard crate, while using Facet's reflection capabilities instead of serde.

Features

• Compact binary format optimized for size
• Byte-for-byte compatibility with the postcard crate
• no_std support with the alloc feature
• Zero-copy deserialization where possible

Usage

use facet::Facet;
use facet_postcard::{to_vec, from_slice};

#[derive(Debug, Facet)]
struct Message {
    id: u32,
    payload: Vec<u8>,
}

// Serialize
let msg = Message { id: 42, payload: vec![1, 2, 3] };
let bytes = to_vec(&msg).unwrap();

// Deserialize
let decoded: Message = from_slice(&bytes).unwrap();

For no_std environments without an allocator, use to_slice:

# use facet::Facet;
# #[derive(Debug, Facet)]
# struct Message { id: u32, payload: Vec<u8> }
# let msg = Message { id: 42, payload: vec![1, 2, 3] };
let mut buf = [0u8; 64];
let used = facet_postcard::to_slice(&msg, &mut buf).unwrap();

Feature Flags

• std (default): Enables standard library support
• alloc: Enables heap allocation without full std (for no_std with allocator)

Sponsors

Thanks to all individual sponsors:

...along with corporate sponsors:

...without whom this work could not exist.

Special thanks

The facet logo was drawn by Misiasart.

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.