2021 State of the API Report

As far as architectural styles for APIs are concerned, a sweeping majority of respondents (94%) use REST; of those, nearly half said that they not only use REST, but that they “use it and love it.” The majority of participants are aware of webhooks, WebSockets, GraphQL, and SOAP, but none of these have seen the same level of adoption as REST among our participants.

We also asked folks which API specifications they know, use, and love, and JSON Schema was by far the top specification in use, cited by three-quarters of respondents. The next most popular specifications were Swagger 2.0 (54%) and OpenAPI 3.0 (40%).

We posed the question, “What technologies are you most excited about using over the next year?” Microservices (58%) and Kubernetes (50%) led the way, just as they did in 2020. Rounding out the top five are containers (46%), serverless architecture (44%), and GraphQL (35%).

We asked survey-takers where they gained most of their knowledge about APIs. Most respondents (62%) learned about APIs on the job or from coworkers. Documentation, online resources, communities, and blogs proved a bit more useful, according to our respondents, than in-person learning like coding schools or conferences.