For the article “How to Tailor my Process-based Model? Dynamic Identifiability Analysis of Flexible Model Structures” (Pilz et al., submitted) a flexible simulation environment is coupled with an algorithm for dynamic identifiability analysis to form a diagnostic tool for process-based model building. This software publication provides the simulation environment ECHSE along with the new WASA engine. The latter was developed and employed for the associated research article. The original ECHSE software was introduced by Kneis (2015) and can be obtained from http://echse.github.io/.