We heavily utilise Jira at my place of work and one of our non IT based departments use it in their business processes. It was chosen to replace a custom developed, unreliable .NET application and apart from minor bending to suit the processes Jira is an excellent replacement. It's also far more reliable, far easier to keep up-to-date and runs on Linux!
In the latest update I had a chance to really push the new version of the Jira Automation Plugin, which is a free and open source plugin. Written by Atlassian to support their internal processes, It's a little nugget of awesome that has really extended what we can do without writing bulk custom code.
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