Business Logic Patterns

Orchestrator for structured business logic in Rails.

Skill Routing

Need	Skill	Use When
Typed operations	active-interaction-coder	Creating business operations, refactoring service objects
State machines	aasm-coder	Implementing workflows, managing state transitions

When to Use Each

ActiveInteraction

Use for operations - things that happen once:

• User registration
• Order placement
• Payment processing
• Data imports
• Report generation

# Example: One-time operation with typed inputs
outcome = Users::Create.run(email: email, name: name)

AASM

Use for state management - things with lifecycle:

• Order status (pending → paid → shipped)
• Subscription state (trial → active → cancelled)
• Document workflow (draft → review → published)
• Task status (todo → in_progress → done)

# Example: Stateful entity with transitions
order.pay!  # pending → paid
order.ship! # paid → shipped

Combined Pattern

Often used together - interactions trigger state changes:

module Orders
  class Process < ActiveInteraction::Base
    object :order, class: Order

    def execute
      order.process!  # AASM transition
      fulfill_order(order)
      order
    end
  end
end

Setup

# Gemfile
gem "active_interaction", "~> 5.3"
gem "aasm", "~> 5.5"

Quick Reference

ActiveInteraction:

• .run - Returns outcome (check .valid?)
• .run! - Raises on failure
• compose - Call nested interactions

AASM:

• .event! - Transition or raise
• .event - Transition or return false
• .may_event? - Check if transition valid
• .aasm.events - List available events

Related Skills

• event-sourcing-coder - Record domain events from state transitions