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