API-first concepts

In general, API-first design is a software development approach in which API design is prioritized. With that in mind, it is possible to generate gains in scalability, flexibility, agility, and performance for your system. When opting for API-first design, developers can facilitate discussions with stakeholders such as their internal team, clients, or any other teams within the organization who wish to consume the API. This mutual collaboration allows the team who is building the API to create user stories, mock-ups, and documentation.

There are a few tools that use an API description language to help teams adopt an API-first technique. This description language helps create a balance around the contract, which will be used by the API. Basically, writing a well-defined contract means that some considerable time will be spent on the API's design.

API-first design brings various benefits, such as the following:

• Development teams can work in parallel: The same SOA approach applies to the API-first strategy. An alignment called contract enables teams to do their work in parallel, since there is an agreement to use the contract. Due to this, developer teams don't have to wait for downstream systems to finish, for instance. All parts can start in parallel, while following the contract.
• Reduces the cost of developing apps: Thinking of APIs first often means that problems are solved, even before concrete implementation, since this strategy allows teams to see the big picture of the problem and perhaps the architecture that is going to be utilized in the API. This will avoid coding unnecessary services and apps.
• Reduces time to market: Once there is a vision being ruled on a business, testing a new hypothesis is quite simple and fast due to the API's ecosystem. Considering that the API strategy is aligned with a Continuous Integration (CI) tool and a Continuous Delivery (CD) process, any change can go live.
  

• Enables good developer experiences: This is part of the scope of the API-first strategy. The APIs are well-documented, used in businesses, and are easy to consume, which creates a good atmosphere for developer teams, since they then understand what the API does.
• Mitigates the risk of failure: Based on reliability, consistency, and ease of use, API-first design directly reduces the risk of failure.