application_helper.rb

def feature_enabled?(feature)
  FeatureFlag.enabled?(feature, current_organization)
end

feature_flag.rb

class FeatureFlag < ApplicationRecord
  serialize :organization_ids, Array

  scope :enabled, -> { where(enabled: true) }

  before_save :normalize_name

  validates_presence_of :name

  def self.enabled?(name, organization)
    feature = FeatureFlag.find_by(name: name.to_s)
    return false if feature.blank?

    normalized_ids = feature.organization_ids.map { |i| i.to_s }
    normalized_ids.include?(organization.id.to_s) && feature.enabled?
  end

  def organization_names
    Organization.where(id: organization_ids).pluck(:name)
  end

  def enable!
    update(enabled: true)
  end

  def disable!
    update(enabled: false)
  end

  private

  def normalize_name
    self[:name] = name.downcase.underscore
  end
end

schema.rb

  create_table "feature_flags", force: :cascade do |t|
    t.string "name", limit: 255
    t.text "organization_ids"
    t.boolean "enabled", default: true
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.index ["name"], name: "index_feature_flags_on_name"
  end