activerecord-ulid

A :ulid attribute type for Active Record. Every record gets its own ULID the moment it's built: sortable, unique, and readable in a URL.

Requires Ruby 4.0+ and Active Record 8.1+.

gem "activerecord-ulid"

ULIDs live in string columns:

create_table :users, id: :string do |t|
  t.string :invite_code
end

class User < ApplicationRecord
  attribute :id, :ulid
end

User.new.id # => "01JBQ8Z3X4M6V2N9R7T5K1W0HD"

Prefix them, Stripe style:

attribute :id, :ulid, prefix: "usr_" # => "usr_01JBQ8Z3X4M6V2N9R7T5K1W0HD"

Options:

• prefix: prepended to the ULID.
• nullable: true (or initial: false) leaves nil alone: no ULID is generated.
• default: given explicitly wins over the generated ULID.

Assigning nil to a generating attribute gives it a fresh ULID.

$ bundle exec rake test                 # padded_cell, Rails 8.1
$ RAILS_VERSION=edge bundle exec rake   # Rails main
$ dictator lint .

MIT. See LICENSE.txt.