These are the arguments that conform a BuiltinData in Plutus:

data Data =
  Constr Integer [Data]
| Map [(Data, Data)]
| List [Data]
| I Integer
| B BS.ByteString
  deriving stock (Show, Eq, Ord, Generic)
  deriving anyclass (NFData)

So we can define an arbitrary mapping for these types

bigint -> I
string -> B
Map    -> Map
list   -> List

Note: We need to wrap it in an object to prevent circular references