# Strict encoding library

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Deterministic binary serialization for client-side-validation.

This library implements **strict encoding** standard, defined by
[LNPBP-7](https://github.com/LNP-BP/LNPBPs/blob/master/lnpbp-0007.md).
Strict encoding is a binary conservative encoding extensively used in
client-side-validation for deterministic portable (platform-independent)
serialization of data with a known internal data structure. Strict encoding
is a schema-less encoding.

As a part of strict encoding, crate also includes implementation of
network address **uniform encoding** standard
([LNPBP-42](https://github.com/LNP-BP/LNPBPs/blob/master/lnpbp-0042.md)),
which allows representation of any kind of network address as a fixed-size
byte string occupying 37 bytes. This standard is used for the strict
encoding of networking addresses.

Client-side-validation is a paradigm for distributed computing, based on top of
proof-of-publication/commitment medium layer, which may be a bitcoin blockchain
or other type of distributed consensus system.

The development of the library is supported by
[LNP/BP Standards Association](https://lnp-bp.org).

The library is designed after Peter Todd concepts of proofmarshall and
serialization principles for client-side-validated data and Dr Maxim Orlovsky
idea of universal network encodings. Both were shaped into the standards and
implemented as a part of this library by Dr Maxim Orlovsky.

## Documentation

Detailed developer & API documentation for the library can be accessed
at <https://docs.rs/strict_encoding/>

To learn about the technologies enabled by the library please check
[slides from our tech presentations](https://github.com/LNP-BP/FAQ/blob/master/Presentation%20slides/)
and [LNP/BP tech talks videos](https://www.youtube.com/channel/UCK_Q3xcQ-H3ERwArGaMKsxg)

## Usage

To use the library, you just need to reference a latest version, in
`[dependencies]` section of your project `Cargo.toml`.

```toml
strict_encoding = "2.5"
```

If you are using other client-side-validation libraries, consider importing
just a single [`client_side_validation`] library which re-exports all of them,
including the current one.

Library defines two main traits, [`StrictEncode`] and [`StrictDecode`],
which should be implemented on each type that requires to be represented
for client-side-validation.

Library exports derivation macros `#[derive(StrictEncode, StrictDecode)]`,
which are a part of [`strict_encoding_derive`] sub-crate and controlled by a
default feature `derive`. Finally, it implements strict encoding traits for main
data types defined by rust standard library and frequently used crates; the
latter increases the number of dependencies and thus can be controlled with
feature flags:

- `chrono` (used by default): date & time types from `chrono` crate
- `miniscript`: types defined in bitcoin Miniscript
- `crypto`: non-bitcoin cryptographic primitives, which include Ed25519
  curve, X25519 signatures from `ed25519-dalek` library and pedersen
  commitments + bulletproofs from `grin_secp256k1zkp` library. Encodings for
  other cryptography-related types, such as Secp256k1 and hashes, are always
  included as a part of the library - see NB below.

This crate requires `bitcoin` as an upstream dependency since many of
strict-encoded formats are standardized as using *bitcoin consensus
encoding*.

## Contributing

Contribution guidelines can be found in [CONTRIBUTING](../CONTRIBUTING.md)

## Licensing

The libraries are distributed on the terms of Apache 2.0 opensource license.
See [LICENCE](LICENSE) file for the license details.

[`client_side_validation`]: https://crates.io/crates/client_side_validation

[`strict_encoding_derive`]: https://crates.io/crates/strict_encoding_derive