Within our deployment pipeline, we have a need to deploy to multiple customer environments, and manage secrets specifically in a way that integrates well with AWS, Kubernetes Secrets, Terraform and our pipelines ourselves.

Jenkins offered us the ability to choose one of a number of credentials/secrets management approaches, and models secrets as a more dynamic concept that GitHub Actions provided.

Additionally, we are operating Jenkins within our development Kubernetes cluster as a kind of system-wide orchestrator, allowing us to use Kubernetes pods as build agents, avoiding the ongoing direct costs associated with GitHub Actions minutes / per-user pricing. Obviously as a consequence we take on the indirect costs of maintain Jenkins itself, patching it, upgrading etc. However our experience with managing Jenkins via Kubernetes and declarative Jenkins configuration has led us to believe that this cost is small, particularly as the majority of actual building and testing is handled inside docker containers and Kubernetes, alleviating the need for less supported plugins that may make Jenkins administration more difficult.

Jenkins is a pretty flexible, complete tool. Especially I love the possibility to configure jobs as a code with Jenkins pipelines.

CircleCI is well suited for small projects where the main task is to run continuous integration as quickly as possible. Travis CI is recommended primarily for open-source projects that need to be tested in different environments.

And for something a bit larger I prefer to use Jenkins because it is possible to make serious system configuration thereby different plugins. In Jenkins, I can change almost anything. But if you want to start the CI chain as soon as possible, Jenkins may not be the right choice.