Managing the challenges of event sourcing : Versioning and incorrect states

Abstract: Event sourcing has caught the interest of many developers due to desirable features such as an implicit audit log and a simplified database design. This thesis presents a case study with a focus on managing the challenges of versioning and correcting incorrect states. The techniques upcasting and support multiple versions are investigated for handling versioning within event sourcing. Partial and full reversal techniques are applied to investigate the correction of incorrect states. The techniques will be implemented within an event sourcing prototype written in F# to demonstrate how the techniques behave in practice, which can be of use for developers that want to endeavor into event sourcing projects. The results of the study show that all investigated techniques can handle the associated challenges. The comparison of techniques shows the advantages and disadvantages associated with the techniques when implemented in the prototype.