Extending our APIs Safely

Building your API properly

So far, we’ve strongly advocated the following strategy:

• Building many small components.
• Managing those components through dependencies.

When this strategy is working well, it simplifies our job by limiting the scope of what we need to understand to make any given change.

This strategy can become a big mess fueled by cascading dependencies in a hurry if we’re not careful with how we build our APIs, though. Specifically, maintaining a healthy ecosystem is difficult if each release of an API breaks compatibility with old API versions.

Breaking changes have several different forms:

• An API can add requirements to input parameters, such ...