Introduction In this article, I would like to introduce to Spring Modulith. And I will resolve some questions such as What is it? Why I have to use?. The Idea of the monolith start with: Martin Fowler (2015) - “Monolith First”: “you shouldn’t start a new project with microservices, even if you’re sure your application will be big enough to make it worthwhile. .” [ˆ1]