starting a new game project? don't forget to add these!

top ten

• The core loop! Make sure it's prototyped and fun before wasting any time.
• A way of assigning IDs and specific instance IDs for comparison and identification.
• A translation. Embed no strings into the code. Instead use keys that retrieve a translation from a spreadsheet. This way, your text is separate from your code and easier to edit. It's not that much more effort to ensure changing the language works, so might as well. If you only know one language, use Pig Latin or just English with special characters, etc, for testing purposes.
• Version control.
• Automated testing.
• A GDD
• A style guide.
• Documentation.
• Good debugging system. Add in cheats (god mode, infinite money, etc), skippable intro and cutscenes, and a way to check and edit in-game values.
• Make input feel good. Responsive controls, smooth movement, etc.
• A process - set granular goals, hold meetings with yourself, reevaluate your schedule, whatever you need to do to make consistent and meaningful process towards completion.
• Save/load, serialization.
• Game time - logic time and draw time