Towards Abstract Test Execution in Early Stages of Model-driven Software Development Topics: Domain-Specific Modeling; Hybrid Multi-Modeling Approaches; Meta-Modeling: Foundations and Tools; Model Execution and Simulation; Model-Based Testing and Validation; Syntax and Semantics of Modeling Languages In Proceedings of the 8th International Conference on Model-Driven Engineering and Software Development MODELSWARD - Volume 1, 216-226, 2020 , Valletta, Malta