Background job retry strategies

                  class ProcessPaymentWorker
  include Sidekiq::Worker

  sidekiq_options queue: :critical, retry: 10

  sidekiq_retry_in do |count, exception|
    case exception
    when PaymentGatewayTimeoutError
      # Exponential backoff for transient errors
      (count ** 4) + 15
    when PaymentValidationError
      # Fast fail for validation errors
      :kill
    else
      # Default: exponential backoff
      (count ** 2) + 15
    end
  end

  def perform(payment_id)
    payment = Payment.find(payment_id)

    # Idempotency check
    return if payment.processed?

    gateway = PaymentGateway.new
    result = gateway.process(payment)

    payment.update!(
      status: 'processed',
      processed_at: Time.current,
      gateway_transaction_id: result.transaction_id
    )
  rescue PaymentGatewayTimeoutError => e
    Rails.logger.warn("Payment gateway timeout for payment #{payment_id}, will retry")
    raise e
  rescue StandardError => e
    Rails.logger.error("Payment processing failed for #{payment_id}: #{e.message}")
    payment.update(status: 'failed', error_message: e.message)
    raise e
  end
end