Application Program Interfaces is the enabler of today’s technology shifts: SaaS, cloud computing, container orchestration, distributed applications, serverless computing, and even machine learning.
The API design first approach advocates for designing the API’s contract first before writing any code, with the use of API specification formats (Swagger, OpenAPI) before the source-code exists. With code first we generate the definition afterwards.
Both approaches have pros and cons.
API first require an organizational wide buy-in. Code first often lead to bottlenecks, because the respective unit of work need to be finished before other can use them.
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