naming-conventions

Naming Conventions

Database Columns

Type	Convention	Good	Bad
Boolean	positive, no is_/has_	active, email_verified	is_active, has_email
Datetime	*_at	published_at, expired_at	publish_date, expiry
Date	*_on	birthday_on, hired_on	birthday, hire_date
Foreign key	singular _id	user_id	users_id
Enum	singular	status, role	statuses

Models & Tables

Entity	Convention	Example
Model	singular CamelCase	Post
Table	plural snake_case	posts
File	snake_case	post.rb
Concern (model-specific)	ModelName::ConcernName	Task::StatusTransitions
Concern (shared)	ConcernName	Notifiable

Controllers

Entity	Convention	Example
Class	plural CamelCase + Controller	Admin::UsersController
File	snake_case	app/controllers/admin/users_controller.rb
Actions	REST only	index, show, new, create, edit, update, destroy

Jobs & Mailers

Entity	Convention	Example
Job	+ Job	SendWelcomeEmailJob
Mailer	+ Mailer	UserMailer

Migrations

Present tense verb + target:

• add_published_at_to_posts
• create_tasks
• remove_legacy_column_from_accounts

Git

Entity	Format	Example
Branch	issues/<id>	issues/42
Commit	[#id] Message	[#42] Fix login timeout
No issue	[fix] Message	[fix] Fix typo
PR title	[#id] Description	[#42] Add renewal notifications

Class Methods

# Good — class << self
class << self
  def find_active
    where(active: true)
  end
end

# Bad — def self.method
def self.find_active
  where(active: true)
end

Enum Usage

# Good — predicate
task.pending?
task.in_progress?

# Good — scope
Task.status_pending
Task.status_in_progress

# Bad
task.status == "pending"
Task.where(status: :pending)