>not totally sure how to achieve it [replaceability]
One of the most crucial keys is: make your code greppable. For example, don't treat OOP classes as a license to use generic method names ("add", "set", "close", etc.), or it'll be difficult to weed those classes out.
One of the most crucial keys is: make your code greppable. For example, don't treat OOP classes as a license to use generic method names ("add", "set", "close", etc.), or it'll be difficult to weed those classes out.