[kevingadd]

fwiw, it's possible to use LINQ in games no problem if you provide your own implementation(s) of the core LINQ methods you care about. I'm using LINQ and async/await in my game with no problems (~900fps, one short gen0/gen1 GC every 70 seconds or so) since I did the work to write zero-allocation versions of the basic operators like Select and Where. The design of LINQ is such that the C# compiler will use whatever implementation of the operator(s) is available when it converts your SQL-y queries into actual code.

I suspect the BCL doesn't include zero-allocation query operators because they generalize poorly, but I'm not sure. Zero-allocation query operators end up looking like 'ZeroAllocSelect<TEnumerable, TSource, TResult> Select (this TEnumerable seq, Func<TSource, TResult> func) where TEnumerable : IEnumerable<TSource>' which is obviously not trivial for the JIT to compile (or trivial to write)

The closures it creates for your queries are kind of a pain though. It's possible that will have improved in NET8 or NET9 because the allocation rules for delegates were recently revised to allow more optimizations, but I don't know if that was fixed.

[starburst]

I actually love the syntax if only it didn't alloc, is your implementation open source?