Changes to a crontab on a production system have a large functional impact and need to be reversible and version controlled. There is no point in developing something on a development system that will eventually be potentially catastrophic in production for this reason. Before coding anything, you need to make sure that the crontab file is version managed and that anything you develop conforms to some kind of change management regulation.

If you can't identify who is responsible for the rules of the relevant change management process in your organisation, ask the relevant production system administrator for what procedures he/she understands to be in effect to manage the crontab versions for the relevant system. I venture to suggest that only then can you safely design your code, let alone build it.

Update: in other words, any module you choose to use will therefore need a wrapper around it that conforms to site procedures.