Installation

Requirements

• Ruby >= 3.1
• Rails ~> 7.1
• PostgreSQL 16+
• UUID primary keys on host models that include Schedulable

Setup

Add the gem to your Gemfile:

gem 'whittaker_tech-aeon'

Install the bundle:

bundle install

Run the install generator (copies the initializer and migrations into your app):

rails generate whittaker_tech:aeon:install

Optionally edit the generated initializer at config/initializers/aeon.rb to customize settings.

Run the copied migrations to create the wt_aeon schema and tables:

rails db:migrate

What the Generator Creates

The install generator copies:

1. Initializer (config/initializers/aeon.rb) — a WhittakerTech::Aeon.configure block with sensible defaults
2. Migrations — creates the wt_aeon PostgreSQL schema with three tables:
   • wt_aeon.allocations — immutable temporal laws
   • wt_aeon.occurrences — materialized predictions with GiST-indexed tstzrange
   • wt_aeon.overrides — surgical single-instance deviations

Host Model Requirements

Any model that includes WhittakerTech::Aeon::Schedulable must use UUID primary keys:

class CreateLessons < ActiveRecord::Migration[7.1]
  def change
    create_table :lessons, id: :uuid do |t|
      t.string :title, null: false
      t.timestamps
    end
  end
end

This is required because all Aeon foreign keys and polymorphic IDs are UUIDs.