ruby

Rails.application.config.middleware.insert_before 0, Rack::Cors do
  # Development CORS - allow any localhost
  allow do
    origins(
      /http:\/\/localhost:\d+/,
      /http:\/\/127\.0\.0\.1:\d+/,

class Board < ApplicationRecord
  has_many :cards, dependent: :destroy
  belongs_to :owner, class_name: "User"

  validates :name, presence: true
end

<%= turbo_frame_tag dom_id(contact) do %>
  <tr class="contact-row">
    <td><%= contact.name %></td>
    <td><%= contact.email %></td>
    <td><%= contact.role.titleize %></td>
    <td class="actions">

# Gemfile
group :development do
  gem 'rack-mini-profiler'
  gem 'memory_profiler'
  gem 'stackprof'  # For flamegraphs
  gem 'bullet'     # N+1 detection

class Import < ApplicationRecord
  include ActionView::RecordIdentifier

  enum status: { pending: 0, processing: 1, completed: 2, failed: 3 }

  has_one_attached :file

module ApplicationCable
  class Connection < ActionCable::Connection::Base
    identified_by :current_user

    def connect
      self.current_user = find_verified_user

class Problem
  DEFAULT_TYPE = "https://api.example.com/problems/about:blank".freeze

  attr_reader :type, :title, :status, :detail, :instance, :extensions

  def initialize(status:, title:, detail: nil, type: nil, instance: nil, extensions: {})

require "loofah"

class HtmlSanitizer
  ALLOWED_TAGS  = %w[p br a strong em ul ol li blockquote code pre h2 h3].freeze
  ALLOWED_ATTRS = %w[href title].freeze
  SAFE_SCHEMES  = %w[http https mailto].freeze

class ExternalApiClient
  def fetch_user_data(user_id)
    ActiveSupport::Notifications.instrument(
      'api.external_service',
      service: 'user_service',
      operation: 'fetch_user',

class ActivityPanelController < ApplicationController
  def show
    @project = Project.find(params[:project_id])
    @events = @project.events.order(created_at: :desc).limit(50)

    latest = @events.maximum(:updated_at)

class Comment < ApplicationRecord
  belongs_to :post
  belongs_to :author, class_name: 'User'

  # Automatically broadcast changes to all subscribers of this post
  after_create_commit -> { broadcast_append_to post, target: "comments" }

class UserNotificationJob < ApplicationJob
  queue_as :default

  # Retry up to 5 times with exponential backoff
  retry_on StandardError, wait: :exponentially_longer, attempts: 5