Code Style

Consistency and simplicity are the most important principles.
Keep game logic out of React, and in game logic classes.
Limit the use of functions outside of classes. I.e. Each function should probably belong to some even if it's just a static function.
Be precise in your use of access modifiers. If a function does not need access to an instance, make it static. If it doesn't need to be public (which all fields and functions in typescript are by default), then mark it as private. Use const unless the variable will be modified.
Annotate all return types of functions.
Rarely annotate the types of locals.
Briefly document all public fields and methods and classes with a description of their purpose.
In method bodies, group similar declarations. Eg group all hook declarations, followed by all effect calls when writing functional React components.
Group methods in classes by their visibility. public methods together, private methods together.
When something is optional, use undefined rather than null, for consistency.
Avoid excessive creation of arrays and objects in hot sections of code, particularly in the renderer.
Classes should have a tighly scoped purpose.
Avoid singletons, and React Context.
When possible, avoid repeating yourself.
Try to keep your functions under 10 statements. 20-30 for really complicated functions.

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