Mutating application state

GraphQL mutations are the actions that cause side effects in your systems because they change the state of a particular resource that your UI cares about. What's interesting about mutations is that they care about side effects that happen to your data as a result of a change in the state of something. For example, if you change the information of a user, this will certainly impact the screen that displays the user information. However, it could also impact a listing screen that shows the information of several users.

Let's see what a mutation looks like:

mutation changeTodoStatus($input: ChangeTodoStatusInput!) {
  changeTodoStatus(input: $input) {
    todo {
      title 
      status
    }
    user {
      todos { 
        title 
  ...