- Everything can be changed.
- Creating, extending and sharing is good and should be as easy as possible.
- All tests should pass.
- Names should be meaningful.
- Comments should express intent.
- Don't repeat yourself.
- Do the simplest thing possible.
1. Can also be thought of as, "everything can be refactored". If a module can be rewritten to make it cleaner, simpler or more readable, it should.
2. An open-source principle, but it should also apply to objects in the game: monsters, items, powers, special levels and professions.
3. Irrelevant and/or obsolete tests can be removed.
6. From Pragmatic Programming - Extreme Programming calls this the "Once and Only Once" principle.
7. An Extreme Programming principle.