1. A computer-implemented method for transforming scoreable transaction data into a financial data feature for use in assessing credit risk, the financial data feature being extracted from the scoreable transaction data, the method comprising: obtaining the scoreable transaction data from a data source; and performing a set of operations on the scoreable transaction data to transform the scoreable transaction data into the financial data feature, the set of operations being selected only from a predefined set of classes of operations, the set of predefined classes of operations being arranged in a predefined order of precedence, wherein each operation in the set of operations is performed in an order based on the predefined order of precedence of a class associated with the each operator, the set of predefined classes of operations including at most five classes of operations, the five classes of operations being a data structure class, an atomic transformation class, an entity transformation class, a time transformation class, and a joining operator class, wherein performing the set of operations includes first performing a data structure operation associated with the data structure class.