During the Shopify theme development process it may be appropriate to have features change slightly depending on whether they’re being used by a customer, a developer or a test suite. For example, if we have an integration in our store, we might want to send API requests to a testing endpoint whilst developing, or running tests on a staging theme, before connecting to a live endpoint when we publish the changes. We can’t trust that we’ll always remember to change this endpoint back to live before deploying to a live theme, so we can avoid the risk by using an environment dependent setting to control this.