The pipeline we designed has at least two significant shortcomings. It is not aware of branches, and it is not in source control. Every time we instructed Jenkins to use the git step, it pulled the latest commit from the master branch. While that might be OK for demos, it is unacceptable in real-world situations. Our pipeline must pull the commit that initiated a build from the correct branch. In other words, no matter where we push a commit, that same commit must be used by the pipeline.
If we start processing all commits, no matter from which branch they're coming, we will soon realize that it does not make sense always to execute the same stages. As an example, the release and deploy stages should be executed only if a commit is made to the master branch. Otherwise, we'd create a new production release always, even if...