SCRU128: Sortable, Clock and Random number-based Unique identifier

SCRU128 ID is yet another attempt to supersede [UUID] for the users who need decentralized, globally unique time-ordered identifiers. SCRU128 is inspired by [ULID] and [KSUID] and has the following features:

• 128-bit unsigned integer type
• Sortable by generation time (as integer and as text)
• 25-digit case-insensitive textual representation (Base36)
• 48-bit millisecond Unix timestamp that ensures useful life until year 10889
• Up to 281 trillion time-ordered but unpredictable unique IDs per millisecond
• 80-bit three-layer randomness for global uniqueness

```rust // generate a new identifier object let x = scru128::new(); println!("{x}"); // e.g., "036z951mhjikzik2gsl81gr7l" println!("{}", x.to_u128()); // as a 128-bit unsigned integer

// generate a textual representation directly println!("{}", scru128::new_string()); // e.g., "036z951mhzx67t63mq9xe6q0j" ```

See [SCRU128 Specification] for details.

Crate features

Default features:

• std configures Scru128Generator with the system clock. Without std, this crate provides limited functionality available under no_std environments.
• rand enables a blanket implementation for rand::RngCore to use the conforming random number generators with Scru128Generator.
• default_rng (implies std and rand) configures Scru128Generator with the default random number generator.
• global_gen (implies default_rng) enables the process-wide default global generator and the new() and new_string() functions.

Optional features:

• serde enables serialization/deserialization via serde.

License

Licensed under the Apache License, Version 2.0.

See also

• docs.rs/scru128