Dealing with closed APIs can be so frustrating! One minute you’re excited to start a new project, the next, you realize you have to integrate with a closed API that’s light on documentation. When you have no clue what the API even does or where to begin, it’s easy to feel blocked. For this reason, we’ve picked up some best practices that can smooth out your closed API integration. But first, let’s understand the main open vs. closed API differences and the various reasons why you might find yourself needing to integrate with a closed API.