When developing corporate-level business applications (Enterprise Scale) customers often requires implementing support for extensibility of the application object model not modifying the system source code. Use of extensible domain model allows for development of new functionality without additional effort and overheads:

1) the application will be used for a more lengthy period
2) the system workflow can be modified over time when changing external factors
3) “setting” the application to fit specifics of an enterprise where it has been deployed.
The most simple and cost effective way to achieve the required functionality would be implementing extensible business entities in an application with the support of custom fields.

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