  DevOps is a combination of methodologies and tools that improves the software
development, build, deployment, and monitoring processes by shortening its
lifecycle and improving software quality. Part of this process is CI/CD, which
embodies mostly the first parts, right up to the deployment. Despite the many
benefits of DevOps and CI/CD, it still presents many challenges promoted by the
tremendous proliferation of different tools, languages, and syntaxes, which
makes the field quite challenging to learn and keep up to date. Software
repositories contain data regarding various software practices, tools, and
uses. This data can help gather multiple insights that inform technical and
academic decision-making. GitHub is currently the most popular software hosting
platform and provides a search API that lets users query its repositories. Our
goal with this paper is to gain insights into the technologies developers use
for CI/CD by analyzing GitHub repositories. Using a list of the
state-of-the-art CI/CD technologies, we use the GitHub search API to find
repositories using each of these technologies. We also use the API to extract
various insights regarding those repositories. We then organize and analyze the
data collected. From our analysis, we provide an overview of the use of CI/CD
technologies in our days, but also what happened in the last 12 years. We also
show developers use several technologies simultaneously in the same project and
that the change between technologies is quite common. From these insights, we
find several research paths, from how to support the use of multiple
technologies, both in terms of techniques, but also in terms of human-computer
interaction, to aiding developers in evolving their CI/CD pipelines, again
considering the various dimensions of the problem.
