@ngneat/dag is designed to assist in creating and managing a directed acycylic graph model in an Angular application. You can think of a DAG as a workflow where a user adds steps and based on given criteria continues on to the next step or steps. With this library, you can add or remove steps to the DAG and the model will be properly updated. With this part of the workflow being managed by the service, you can focus on what the workflow does rather than how to let the user build it. The first thing to note is that this service is not provided in the root of the Angular application. The reasoning for this is because each time a DAG model needs to be created, a new instance of the service should be created. This means that when you import the service into a component, you should add it to the component's providers array.