@article {2022:jwe,
	title = {A Large-scale Empirical Assessment of Web API Size Evolution},
	journal = {Journal of Web Engineering},
	volume = {21},
	year = {2022},
	month = {November},
	pages = {1937{\textendash}1980},
	abstract = {Like any other type of software, also Web Application Programming Interfaces (APIs) evolve over time. In the case of widely used API, introducing changes is never a trivial task, because of the risk of breaking thousands of clients relying on the API. In this paper we conduct an empirical study over a large collection of OpenAPI descriptions obtained by mining open source repositories. We measure the speed at which Web APIs change and how changes affect their size, simply defined as the number of operations. The dataset of API descriptions was collected over a period of one year and includes APIs with histories spanning across up to 7 years of commits. The main finding is that APIs tend to grow, although some do reduce their size, as shown in the case study examples included in the appendix.},
	keywords = {API Evolution},
	doi = {10.13052/jwe1540-9589.2167},
	url = {https://ieeexplore.ieee.org/document/10246943},
	author = {Fabio Di Lauro and Souhaila Serbout and Cesare Pautasso}
}
@conference {apiace:2022:ecsa,
	title = {To deprecate or to simply drop operations? An empirical study on the evolution of a large OpenAPI collection},
	booktitle = {16th European Conference on Software Architecture (ECSA)},
	volume = {13444},
	year = {2022},
	month = {September},
	pages = {38-46},
	publisher = {Springer},
	organization = {Springer},
	address = {Prague, Czech Republic},
	keywords = {API Analytics, API Evolution},
	doi = {doi.org/10.1007/978-3-031-16697-6_3},
	author = {Fabio Di Lauro and Souhaila Serbout and Cesare Pautasso}
}
@conference {2021:icwe:api-evolution,
	title = {Towards Large-scale Empirical Assessment of Web APIs Evolution},
	booktitle = {21st International Conference on Web Engineering (ICWE2021)},
	year = {2021},
	month = {May},
	pages = {124-138},
	publisher = {Springer},
	organization = {Springer},
	address = {Biarritz, France},
	abstract = {Web Application Programming Interfaces (APIs) decouple the internal implementation of a service from its consumers which can reuse and compose them to rapidly build new applications.
Many Web APIs are described with the OpenAPI Specification (OAS). The goal of our research is to check the feasibility of using API descriptions found in public open source repositories to study how APIs evolve over time. To do so, we collected a large dataset of OAS documents by crawling open source repositories, we parsed the corresponding metadata and measured the API size in order to extract a simple model to track the lifecycle of API artifacts and observe common evolution behaviors. Our preliminary results indicate that only a subset of the APIs changes, but as opposed to the expectation that APIs should only grow to maintain backward compatibility we also detected a number of APIs with a more variable history. We also study the stability of API artifacts over time and whether APIs are more or less likely to change as they age.},
	keywords = {API Evolution, OpenAPI, Web API},
	doi = {10.1007/978-3-030-74296-6_10},
	author = {Fabio Di Lauro and Souhaila Serbout and Cesare Pautasso}
}
