One thing I have been meaning to push out to my game is Unit Testing! With a game so heavily involved in its stats and systems it's very very easy to make mistakes.
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Introducing tests to my RPG game's systems, especially for damage and equipment calculations. One pain point I had while setting this up was the actual testing integration itself.
I actually will admit that I tightly coupled many game systems together. What this means from a less techy perspective is that if I try to load the player for example, it needs data about items. So I try to load the item data too, and that data relies on an item attribute system. I load that which also includes monster attributes, so I have to load monster data too. That requires data about the world. The world needs data about entities and level data... So I now have to fake some map data to load everything.
Overall, I did not design with a modular design in mind for the game. Now this isn't necessarily a super ugly scenario to be in, but it takes time to revisit all the dependency chains that my systems require and setup the testing environment. A mistake I can now keep in mind for the future!
After going through all that, I have a proper testing environment where I now have confidence things will still work even as I keep typing away and developing the game!
Great! Well, not much else to share right now. Back to development work!