# AxHash
AxHash is a fast, deterministic hashing family for Rust, C/C++.
If you only need AxHash in Rust, start with the `axhash` crate from this workspace. It is the simplest entrypoint and re-exports the core engine with a friendlier import path.
## Pick The Right Package
- Rust: `axhash`
- C / C++ / Go / Zig / Swift / Kotlin Native: `axhash-ffi`
- Internal engine / `no_std`: `axhash-core`
## Rust Quick Start
Add the simplest Rust package:
```toml
[dependencies]
axhash = "0.8"
```
Hash raw bytes:
```rust
use axhash::hash;
fn main() {
let digest = hash(b"hello axhash");
println!("{digest:016x}");
}
```
Hash raw bytes with a seed:
```rust
use axhash::hash_with_seed;
fn main() {
let digest = hash_with_seed(b"hello axhash", 0x1234_5678);
println!("{digest:016x}");
}
```
Hash any Rust value that implements `Hash`:
```rust
use axhash::hash_value;
#[derive(Hash)]
struct SessionKey {
account_id: u64,
region_id: u32,
flags: u32,
}
fn main() {
let key = SessionKey {
account_id: 42,
region_id: 7,
flags: 3,
};
let digest = hash_value(&key);
println!("{digest:016x}");
}
```
Use the streaming hasher:
```rust
use axhash::AxHasher;
use std::hash::Hasher as _;
fn main() {
let mut hasher = AxHasher::new_with_seed(0x4444);
hasher.write(b"hello ");
hasher.write(b"world");
println!("{:016x}", hasher.finish());
}
```
Use AxHash with `HashMap`:
```rust
use axhash::AxBuildHasher;
use std::collections::HashMap;
fn main() {
let mut map = HashMap::with_hasher(AxBuildHasher::with_seed(0xfeed_beef));
map.insert("status", "ok");
map.insert("runtime", "fast");
println!("{:?}", map.get("status"));
}
```
Inspect the active backend:
```rust
use axhash::{runtime_backend, runtime_has_aes};
fn main() {
println!("{:?}", runtime_backend());
println!("{}", runtime_has_aes());
}
```
## Workspace Layout
- [axhash-core](crates/axhash-core/README.md): low-level Rust core and `no_std` engine
- [axhash-ffi](crates/axhash-ffi/README.md): stable C ABI
## Benchmarks
Internal Criterion screenshots:
## License
MIT.