@type t() :: %{
  api_key: String.t(),
  environment: :test | :live,
  merchant_account: String.t() | nil,
  timeout: non_neg_integer(),
  connect_timeout: non_neg_integer(),
  max_retries: non_neg_integer(),
  retry_delay: non_neg_integer(),
  checkout_api_version: String.t(),
  management_api_version: String.t(),
  terminal_api_version: String.t(),
  cloud_device_api_version: String.t(),
  bin_lookup_api_version: String.t(),
  disputes_api_version: String.t(),
  payout_api_version: String.t(),
  recurring_api_version: String.t(),
  balance_platform_api_version: String.t(),
  transfer_api_version: String.t(),
  legal_entity_api_version: String.t(),
  capital_api_version: String.t(),
  classic_payment_api_version: String.t(),
  classic_account_api_version: String.t(),
  classic_fund_api_version: String.t(),
  classic_hop_api_version: String.t(),
  classic_notification_api_version: String.t(),
  foreign_exchange_api_version: String.t(),
  open_banking_api_version: String.t(),
  webhook_hmac_key: String.t() | nil,
  user_agent: String.t()
}