The case for hard-coding configuration


It is often argued that software configuration should not be hard-coded as it is important to be able to make configuration changes without deploying a new revision of the software. I consider this to be an Anti-pattern as the problem is with the application deployment process, and moving everything into configuration essentially creates a way of editing the code directly in your production environment. These configuration changes are never tested as they skip your testing and deployment pipeline and therefore result in software failures. This obviously makes the assumption that you are not selling physical packaged software, surely no one does that anymore.

There is still a need for configuration but that comes out of the requirement to have environment specific settings for an application. Data that may be considered configuration should be hard-coded until it becomes apparent that the data is required to be environment specific in which case it can be moved into configuration.

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