The first step in algebraic cryptanalysis is to obtain a system of                                                                                           
polynomial   equations representing a cryptosystem. Even this first                                                                                          
step is surrounded by    many open questions, such as determining the                                                                                        
most effective representation of   different components in a cipher.                                                                                         
We describe the software package Scrypt,     which automates the                                                                                            
tedious aspects of this step and allows easy                                                                                                                 
experimentation with different algebraic models and representations.                                                                                         
Scrypt    separates the task of describing the structure of a                                                                                               
cryptosystem from modeling  the components algebraically. Symbolic                                                                                           
computation is used in this process to   delay attaching algebraic                                                                                           
models to components, and allow the user to           experiment with                                                                                        
different algebraic representations of cipher components later.