This talk marks the beginning of GReTA-ExACT, a new online working group within the GReTA community. The aim of this working group will consist in providing an interdisciplinary forum for exploring the diverse aspects of applied category theory relevant in graph transformation systems and their generalizations, in developing a methodology for formalizing diagrammatic proofs as relevant in rewriting theories via proof assistants such as Coq, and in establishing a community-driven wiki system and …