Cuid2Ex

Cuid2Ex is an Elixir implementation of the CUID2 (Collision-resistant Unique IDentifier) algorithm. It generates secure, collision-resistant IDs optimized for horizontal scaling and performance. The generated IDs are URL-safe, contain no special characters, and have a configurable fixed length.

Features

• Secure, collision-resistant ID generation
• URL-safe output with no special characters
• Configurable ID length (default: 24 characters)
• Zero dependencies (besides Erlang/OTP crypto)

Installation

Add cuid2_ex to your list of dependencies in mix.exs:

def deps do
  [
    {:cuid2_ex, "~> 0.1.0"}
  ]
end

Usage

Basic Usage

Generate a CUID2 with default settings (24 characters):

Cuid2Ex.create()
# => "k0xpkry4lx8tl3qh8vry0f6m"

Custom Length

Generate a longer CUID2 (32 characters):

Cuid2Ex.create(length: 32)
# => "k0xpkry4lx8tl3qh8vry0f6maabc1234"

Create a Generator

For better performance when generating multiple IDs, create a generator function:

generator = Cuid2Ex.init(length: 24)
generator.()
# => "k0xpkry4lx8tl3qh8vry0f6m"

Validation

Validate if a string is a valid CUID2:

Cuid2Ex.cuid?("k0xpkry4lx8tl3qh8vry0f6m")
# => true

Cuid2Ex.cuid?("invalid!")
# => false

Configuration Options

The init/1 and create/1 functions accept the following options:

• :length - Length of generated IDs (default: 24)
• :random - Custom random number generator function
• :counter - Custom counter function
• :fingerprint - Custom fingerprint string