Yelp uses openapi-generator to create REST clients for the Java services within our microservice architecture. Defining the API's in Swagger and auto-generating the client code is a big improvement in understandability and maintainability over what we used to do, which was to write bespoke clients for each microservice.

Openapi-generator is opinionated when it comes to how the data model classes are defined, and the feature set depends on which underlying HTTP library you choose (Jersey, Feign, Retrofit, OkHttp, etc), so we needed to invest some time when getting started to make necessary adjustments. But overall it has proven to be robust and meet our needs.